CHUAS RAWINSONDE HANDBOOK IMS-1500C … 9-756 Rev B June 2009.pdf · sippican b2 radiosonde june...

NWS EHB 9-756

Revision B

CHUAS RAWINSONDE HANDBOOK

IMS-1500C RADIOTHEODOLITE SIPPICAN B2 RADIOSONDE

June 2009

DEPARTMENT OF COMMERCE NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION

NATIONAL WEATHER SERVICE MAINTENANCE, LOGISTICS & ACQUISITION, W/OPS1

1325 EAST-WEST HIGHWAY SILVER SPRING, MD 20910

NWS EHB 9−756 CHUAS RAWINSONDE HANDBOOK

RECORD OF CHANGES

Change Number

Effective Date Initials Date

Entered Remarks

10/03/2007 WLM Initial Release

Rev B 06/02/2009 WLM 06/02/2009 iMetOS Version 4.0.29

CHUAS RAWINSONDE HANDBOOK NWS EHB 9−756

Revision B June 2009 iii Table of Contents

TABLE OF CONTENTS

CHAPTER 1 IMS-1500C SYSTEM METEOROLOGICAL COMPUTER OPERATION..............1-1 1.1 Introduction...................................................................................................................1-1

1.1.1 Observational Procedures .................................................................................1-1 1.1.1.1 Times of Observations ...........................................................................................1-2 1.1.1.2 Transmission of Observations................................................................................1-2 1.1.1.3 Recording and Preserving Observations................................................................1-2 1.1.1.4 CHUAS Meteorological Station Information ...........................................................1-2

1.1.2 IMS-1500C Functional Overview .......................................................................1-7 1.1.2.1 Equipment Overview ..............................................................................................1-7 1.1.2.1.1 Utility Power to the UPS .........................................................................................1-9 1.1.2.2 System Computer.................................................................................................1-11 1.1.2.3 System Software ..................................................................................................1-11 CHAPTER 2 FLIGHT OPERATIONS.........................................................................................2-1

2.1 Launch Sequence ........................................................................................................2-1 2.1.1 Activate the iMet-1500C System Meteorological Computer ..............................2-1 2.1.2 Activate the Sippican B2 Radiosonde................................................................2-1 2.1.3 Activate and Initialize the iMetOS Meteorological Software ..............................2-1

2.1.3.1 Frequency Lock-On................................................................................................2-2 2.1.3.2 File Name Entry......................................................................................................2-3

2.1.4 PreFlight Data Entry and Radiosonde Status Check.........................................2-4 2.1.4.1 PreFlight Data Entry ...............................................................................................2-4 2.1.4.2 Radiosonde Status Check......................................................................................2-9 2.1.4.3 PreFlight Status Check...........................................................................................2-9 2.1.4.4 Save PreFlight Data ...............................................................................................2-9 2.1.4.5 Radiosonde Launch Delay ...................................................................................2-10 2.1.4.6 Radiosonde Second Release...............................................................................2-10 2.1.4.7 Radiosonde Ready for Launch.............................................................................2-10

2.2 Radiosonde ................................................................................................................2-11 2.2.1 Radiosonde Inspection ....................................................................................2-11

2.2.1.1 Replacement B-2 Radiosonde Calibration Files...................................................2-11 2.2.2 Radiosonde Components ................................................................................2-11

2.2.2.1 Pressure Sensor...................................................................................................2-11 2.2.2.1.1 Pressure Sensor Capabilities and Limitations......................................................2-12 2.2.2.2 Temperature Sensor ............................................................................................2-12 2.2.2.2.1 Temperature Sensor Capabilities and Limitations................................................2-12 2.2.2.3 Relative Humidity Sensor .....................................................................................2-13 2.2.2.3.1 Relative Humidity Sensor Capabilities and Limitations ........................................2-13 2.2.2.4 Radiosonde Transmitter and Battery....................................................................2-13 2.2.2.4.1 Radiosonde Transmitter .......................................................................................2-13 2.2.2.4.2 Battery ..................................................................................................................2-13

2.3 Radiosonde Balloon ...................................................................................................2-14


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2.3.1 Balloon Inflation and Performance...................................................................2-14 2.4 Radiosonde (NWS) Balloon Types.............................................................................2-14

2.4.1 Routine Upper-Air Soundings ..........................................................................2-15 2.5 Flight Performance .....................................................................................................2-15 2.6 Balloon Storage and Handling....................................................................................2-16 2.7 Inflation Gases ...........................................................................................................2-16 2.8 Pre-Flight Preparations ..............................................................................................2-16

2.8.1 Flight Train Components .................................................................................2-17 2.8.1.1 Balloon .................................................................................................................2-17 2.8.1.2 Train Cord ............................................................................................................2-17 2.8.1.3 Parachute .............................................................................................................2-18 2.8.1.4 Train Regulator and Unwinder .............................................................................2-18 2.8.1.5 Shock Unit ............................................................................................................2-19 2.8.1.6 Light Stick.............................................................................................................2-20 2.8.1.7 Radiosonde ..........................................................................................................2-20

2.8.2 Flight Train Requirements ...............................................................................2-20 2.8.2.1 High Surface Wind ...............................................................................................2-20 2.8.2.2 Heavy Precipitation ..............................................................................................2-20

2.8.3 Balloon Inflation ...............................................................................................2-20 2.8.3.1 Safety Procedures................................................................................................2-21 2.8.3.2 Proper Inflation Rates...........................................................................................2-21 2.8.3.3 Inflation Procedures .............................................................................................2-21 2.8.3.3.1 First Stage in Inflation...........................................................................................2-21 2.8.3.3.2 Intermediate Inspection ........................................................................................2-21 2.8.3.3.3 Final Inflation ........................................................................................................2-21 2.8.3.3.4 Securing the Balloon ............................................................................................2-21 2.8.3.4 Launch Delays......................................................................................................2-22

2.8.4 Fastening the Flight Train Together.................................................................2-22 2.8.5 Radiosonde B2 Pre-Flight Preparation ............................................................2-23

2.8.5.1 General.................................................................................................................2-23 2.8.5.2 Checkout Assembly..............................................................................................2-23 2.8.5.3 Preflight Baseline .................................................................................................2-25 2.8.5.4 Installing the Hygristor..........................................................................................2-27 2.8.5.5 Battery and Preparation for Sounding ..................................................................2-28

2.9 Transportation of Instrument to Release Point...........................................................2-31 2.10 Final Inspection of Flight Train ...................................................................................2-31 2.11 Final Safety Check .....................................................................................................2-32

2.11.1 Notify the Local Tower .....................................................................................2-32 2.11.2 Radiosonde Launch.........................................................................................2-32

2.12 Flight – Starting the Flight ..........................................................................................2-32 2.12.1 Using the CDU.................................................................................................2-33

2.12.1.1 Flight - Tracking the Radiosonde .........................................................................2-33 2.12.1.2 Flight – Tracking the Radiosonde using the CDU ................................................2-33 2.12.1.3 Flight – End of Flight ............................................................................................2-33


Revision B June 2009 v Table of Contents

2.12.2 Using the System Computer............................................................................2-33 2.12.3 Fair Weather Launches ...................................................................................2-34 2.12.4 Calm Wind Launches.......................................................................................2-34 2.12.5 Heavy Precipitation..........................................................................................2-34 2.12.6 High Winds ......................................................................................................2-34

2.12.6.1 Two Person Technique ........................................................................................2-35 2.12.7 Thunderstorm ..................................................................................................2-35 2.12.8 Delayed Release .............................................................................................2-35

2.13 Maintaining Proper Signal Lock-On............................................................................2-35 2.14 Multiple Releases .......................................................................................................2-36 2.15 Observation’s Success...............................................................................................2-36 2.16 Reasons for Missing Data ..........................................................................................2-37

2.16.1 Weak Signal.....................................................................................................2-37 2.16.2 Interference......................................................................................................2-37 2.16.3 Sensor Failure .................................................................................................2-37 2.16.4 Successful Observation – Some Missing Data................................................2-37 2.16.5 Unsuccessful Observation – Sum of All Missing Data.....................................2-38

2.17 Inflight Procedures .....................................................................................................2-38 2.17.1 IMS-1500C Control Display Unit (CDU) and Workstation Checks...................2-38 2.17.2 SMC CDU and Workstation Checks ................................................................2-38 2.17.3 Tracking Problems...........................................................................................2-38

2.17.3.1 Signal Problems ...................................................................................................2-38 2.17.3.2 Frequency Problems ............................................................................................2-38

2.17.4 IMS-1500C Workstation Checks......................................................................2-39 2.18 Flight Check of the IMS-1500.....................................................................................2-39 2.19 Corrective Actions ......................................................................................................2-39 2.20 Balloon Overhead.......................................................................................................2-40 2.21 Failed Flight................................................................................................................2-40

2.21.1 No Data above Surface Available....................................................................2-40 2.21.2 Data above Surface Available .........................................................................2-41

2.22 Data Checks...............................................................................................................2-41 2.23 Deadlines for Transmission of Observation ...............................................................2-41

2.23.1 Deadlines for Transmitting Coded Messages..................................................2-41 2.24 Coded Message .........................................................................................................2-41

2.24.1 Significant Thermodynamic Levels Parts TTBB and TTDD.............................2-43 2.24.2 Significant Winds Levels parts PPBB and PPDD ............................................2-43 2.24.3 Missing Wind Data...........................................................................................2-43

2.25 WMO Abbreviated Heading........................................................................................2-44 2.25.1 WMO Abbreviated Heading .............................................................................2-44

2.26 Coded Message Breakdown ......................................................................................2-45 2.26.1 Standard Atmosphere Heights.........................................................................2-49 2.26.2 Fixed Levels for Reporting Purposes...............................................................2-49

2.27 Terminating the Observation ......................................................................................2-51 2.28 Termination ................................................................................................................2-52


Table of Contents vi June 2009 Revision B

2.28.1 Automatic Termination.....................................................................................2-52 2.28.2 Manual Termination .........................................................................................2-52

2.29 Archiving the Flight.....................................................................................................2-52 2.30 NWS Archived Files ...................................................................................................2-53 2.31 Monthly Special Problems Archival ............................................................................2-54 2.32 Shutdown Procedures ................................................................................................2-54

CHAPTER 3 INTERMET METEOROLOGICAL OPERATING SYSTEM (iMetOS)....................3-1 3.1 Introduction...................................................................................................................3-1 3.2 Modes of Operation......................................................................................................3-1 3.3 Log Files.......................................................................................................................3-1

3.3.1 Raw Log File......................................................................................................3-1 3.3.2 Processed Log File ............................................................................................3-1

3.4 iMetOS Flight Screen ...................................................................................................3-2 3.4.1 iMetOS Menu Bar ..............................................................................................3-3

3.4.1.1 File..........................................................................................................................3-3 3.4.1.2 Preflight ..................................................................................................................3-3 3.4.1.3 Reports...................................................................................................................3-3 3.4.1.4 Graphs....................................................................................................................3-3 3.4.1.5 View........................................................................................................................3-4 3.4.1.6 Utilities....................................................................................................................3-4 3.4.1.7 Setup ......................................................................................................................3-4 3.4.1.8 Help ........................................................................................................................3-4

3.4.2 iMetOS Toolbar..................................................................................................3-4 3.4.2.1 New ........................................................................................................................3-4 3.4.2.2 Open.......................................................................................................................3-4 3.4.2.3 Load Log ................................................................................................................3-4 3.4.2.4 Preflight ..................................................................................................................3-4 3.4.2.5 Report 1, 2 11, and 12............................................................................................3-5 3.4.2.6 PTU, Wind, T/P ......................................................................................................3-5 3.4.2.7 Reports and Messages ..........................................................................................3-5 3.4.2.8 Physical Values ......................................................................................................3-5 3.4.2.9 Exit .........................................................................................................................3-5 3.4.2.10 Map Scale ..............................................................................................................3-5 3.4.2.11 Change Sonde Type ..............................................................................................3-5

3.4.3 iMetOS Status Bar .............................................................................................3-5 3.4.4 Flight Screen Main Body....................................................................................3-5

3.4.4.1 Receiver Area.........................................................................................................3-6 3.4.4.2 Radiosonde Area....................................................................................................3-7 3.4.4.3 Telemetry Area.......................................................................................................3-7

3.5 iMetOS Graphs.............................................................................................................3-8 3.5.1 Graph Menu Bar ................................................................................................3-8 3.5.2 Graph Toolbar....................................................................................................3-8

3.5.2.1 Editing Data in Graph Mode ...................................................................................3-9 3.5.2.2 PTU Graph ...........................................................................................................3-10


Revision B June 2009 vii Table of Contents

3.5.2.3 Wind Graph ..........................................................................................................3-11 3.5.2.4 T/Log P Graph......................................................................................................3-12

3.5.3 Report Generation ...........................................................................................3-13 3.5.3.1 Report Menu Bar ..................................................................................................3-15 3.5.3.2 Report Toolbar .....................................................................................................3-15

3.5.4 Viewing Physical Values..................................................................................3-16 3.5.4.1 Data Interpolation .................................................................................................3-16

3.5.5 End of Flight.....................................................................................................3-16 3.5.6 Exiting the iMetOS...........................................................................................3-17

3.6 Simulated Flights........................................................................................................3-17 3.6.1 Simulated Flight Procedures............................................................................3-18

CHAPTER 4 SMC UTILITIES ....................................................................................................4-1 4.1 Utilities Menu................................................................................................................4-1

4.1.1 Store Files..........................................................................................................4-2 4.1.2 Restore Files......................................................................................................4-2 4.1.3 Delete Files........................................................................................................4-4 4.1.4 Enable Software Functions................................................................................4-4

4.2 National Climatic Data Center ......................................................................................4-5 4.2.1 Background........................................................................................................4-5

4.2.1.1 NWS Identification File ...........................................................................................4-5 4.2.1.2 NWS Data Record................................................................................................4-15 4.2.1.3 NWS High Resolution Data ..................................................................................4-18 CHAPTER 5 SMC SYSTEM SETUP .........................................................................................5-1

5.1 System Setup ...............................................................................................................5-1 5.1.1 Communication Ports Parameters.....................................................................5-2 5.1.2 Display Color Parameters..................................................................................5-2 5.1.3 System Parameters I .........................................................................................5-3 5.1.4 System Parameters II ........................................................................................5-5 5.1.5 NWS Parameters...............................................................................................5-6 5.1.6 WMO Reports Selection ....................................................................................5-7 5.1.7 WMO Coding Parameters I................................................................................5-8 5.1.8 WMO Coding Parameters II...............................................................................5-9 5.1.9 MetServer Configuration....................................................................................5-9

CHAPTER 6 CDU OPERATING PROCEDURES......................................................................6-1 6.1 General.........................................................................................................................6-1 6.2 Control Display Unit (CDU) ..........................................................................................6-1

6.2.1 User Interface ....................................................................................................6-2 6.2.1.1 Idle State Overview ................................................................................................6-2 6.2.1.1.1 Idle State ................................................................................................................6-2 6.2.1.1.2 Menus.....................................................................................................................6-2 6.2.1.1.3 Keyboard ................................................................................................................6-2 6.2.1.1.4 Direction Controls...................................................................................................6-3 6.2.1.2 Antenna Menu Key.................................................................................................6-3 6.2.1.2.1 Antenna Positioning ...............................................................................................6-4


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6.2.1.2.2 Zero Position ..........................................................................................................6-5 6.2.1.2.3 Antenna (Limited) Search.......................................................................................6-5 6.2.1.2.4 Auto Tracking .........................................................................................................6-6 6.2.1.2.5 Manual Tracking.....................................................................................................6-6 6.2.1.2.6 Calibration ..............................................................................................................6-6 6.2.1.3 Receiver Menu Key ................................................................................................6-7 6.2.1.3.1 Automatic Frequency Control (AFC) On.................................................................6-7 6.2.1.3.2 Manual Frequency Control Off ...............................................................................6-7 6.2.1.3.3 Receiver Search (Automatic Signal Location) ........................................................6-7 6.2.1.3.4 Tune (Manual Tuning) ............................................................................................6-8 6.2.1.3.5 Goto Frequency......................................................................................................6-8 6.2.1.4 System Menu Key ..................................................................................................6-8 6.2.1.4.1 Data........................................................................................................................6-9 6.2.1.4.2 LCD Contrast..........................................................................................................6-9 6.2.1.4.3 Audio Outputs.......................................................................................................6-10 6.2.1.4.4 Volume Level........................................................................................................6-10 6.2.1.4.5 Master Control ......................................................................................................6-10 6.2.1.4.6 Version Information ..............................................................................................6-10 6.2.1.5 Intermediate and Error Screens ...........................................................................6-11 CHAPTER 7 QUALITY CONTROL OF DATA ...........................................................................7-1

7.1 Introduction...................................................................................................................7-1 7.2 Observer Quality Control of Upper-air Soundings........................................................7-1 7.3 Current USA (other) RAOB “THANKS” Report.............................................................7-3

7.3.1 The Raob "Thanks" Reports program consists of four station groups...............7-4 7.3.2 Raob data sets are reported as three data subsets or groups. .........................7-4 7.3.3 Example of “THANKS”.......................................................................................7-5

7.4 Spanish Translated THANKS 2 Page ..........................................................................7-6 7.5 Raob Data Manual Quality Control Reports .................................................................7-6

CHAPTER 8 COMPLETION OF DOCUMENTATION (FORMS) ...............................................8-1 8.1 Introduction...................................................................................................................8-1

8.1.1 Upper-air Forms.................................................................................................8-1 8.2 Completion and Submission of Forms .........................................................................8-1 8.3 WS Form B-29, (Rawinsonde Report)..........................................................................8-1

8.3.1 Entries on WS Form B-29..................................................................................8-1 8.4 WS Form B-85, (Rawinsonde Inventory)......................................................................8-3

8.4.1 Entries on WS Form B-85..................................................................................8-3 CHAPTER 9 STATION SAFETY ...............................................................................................9-1

9.1 Introduction...................................................................................................................9-1 9.2 Upper-Air Safety Issues inside the Office.....................................................................9-1 9.3 The Upper-Air Inflation Building ...................................................................................9-1

9.3.1 Generic Safety Issues for All Inflation Sites.......................................................9-1 9.3.1.1 Outside the Inflation Building..................................................................................9-1 9.3.1.2 Inside the Inflation Building ....................................................................................9-2

9.4 Hydrogen Sites.............................................................................................................9-3 9.5 Safety Issues Prior to Release .....................................................................................9-4


Revision B June 2009 ix Table of Contents

CHAPTER 10 SPECIAL INFLIGHT SITUATIONS...................................................................10-1 10.1 Introduction.................................................................................................................10-1 10.2 Descending and Re-ascending Balloon .....................................................................10-1 10.3 Erratic Temperatures and Relative Humidity Profile ..................................................10-4 10.4 Erratic Wind Data .......................................................................................................10-6 10.5 Data Dropouts ............................................................................................................10-7 10.6 Inaccurate Relative Humidity above Surface Layer .................................................10-11 10.7 Relative Humidity Dry Bias and Environmental Conditions......................................10-13 10.8 Inaccurate Release Detection ..................................................................................10-15 10.9 Sensor Failure ..........................................................................................................10-17 10.10 Leaking Pressure Cell ........................................................................................10-18 10.11 Wetbulb Effect or Evaporative Cooling...............................................................10-18 10.12 Evaluating Flight Termination Point....................................................................10-20 10.13 Pressure Increase since Baseline ......................................................................10-22

CHAPTER 11 CLOUDS & WEATHER CODES.......................................................................11-1 11.1 Introduction.................................................................................................................11-1 11.2 Getting Started ...........................................................................................................11-1 11.3 Amount of Low/Middle Cloud .....................................................................................11-2 11.4 Coding of Low Cloud ..................................................................................................11-2 11.5 Height of Cloud Base above Ground..........................................................................11-3 11.6 Coding of Middle Cloud ..............................................................................................11-4 11.7 Coding of High Cloud .................................................................................................11-4 11.8 Coding of Present Weather ........................................................................................11-5 11.9 Example of Observations .........................................................................................11-12

CHAPTER 12 Communications Architecture & Rawinsonde Quick Guide..............................12-1 12.1 CHUAS Communications Architecture.......................................................................12-1

12.1.1 CHUAS Local Communications Procedures ...................................................12-1 12.2 NWS Email Data Input System (EDIS).......................................................................12-4

12.2.1 Guidance for using EDIS .................................................................................12-8 12.3 Transmission of Upper Air Archive Data to NCDC...................................................12-10

12.3.1 E-Mail Archived Data to NCDC......................................................................12-10 12.3.1.1 Creating the Upper Air Data file .........................................................................12-10 12.3.1.2 CHUAS WMO Station Number, ICAO Call Sign, and WBAN ID ........................12-11

12.3.2 FTP Archive Data to NCDC ...........................................................................12-11 12.3.2.1 Creating the Upper Air Data file .........................................................................12-11 12.3.2.2 FTP the Data File to NCDC................................................................................12-12 12.3.2.3 Storing Archived Files ........................................................................................12-12

12.4 CHUAS IMS-1500 Quick Guide for Rawinsonde Flights..........................................12-13 12.4.1 Bahamas Quick Guide for Rawinsonde Flights .............................................12-13 12.4.2 Barbados Quick Guide for Rawinsonde Flights .............................................12-22 12.4.3 Belize Quick Guide for Rawinsonde Flights...................................................12-30 12.4.4 Curacao Quick Guide for Rawinsonde Flights...............................................12-40 12.4.5 Dominican Republic Quick Guide for Rawinsonde Flights ............................12-50


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12.4.6 Grand Cayman Quick Guide for Rawinsonde Flights ....................................12-59 12.4.7 Jamaica Quick Guide for Rawinsonde Flights ...............................................12-68 12.4.8 San Andres Quick Guide for Rawinsonde Flights..........................................12-76 12.4.9 St. Maarten Quick Guide for Rawinsonde Flights..........................................12-84 12.4.10 Trinidad Quick Guide for Rawinsonde Flights ........................................12-93

12.5 CHUAS IMS-1500 Quick Guide for Rawinsonde Flights (Spanish) .......................12-102 12.5.1 República Dominicana Guía rápida para Radio sonda Vuelos....................12-102

CHAPTER 13 PRECISION DIGITAL BAROMETER ...............................................................13-1 13.1 Precision Digital Barometer - General........................................................................13-1 13.2 PDB Warning Messages ............................................................................................13-2 13.3 Unpacking the Precision Digital Barometer................................................................13-3

13.3.1 Parts List..........................................................................................................13-3 13.3.2 Optional External Temperature Sensor Radiation Shield (ASN G395-2) ........13-3

13.4 Installing the Precision Digital Barometer...................................................................13-3 13.4.1 Installation........................................................................................................13-4 13.4.2 Locating the PDB-1..........................................................................................13-4 13.4.3 Setting up the Rack Mount (Option) ................................................................13-4 13.4.4 Mounting the External Temperature Sensor and Pressure Hose ....................13-5 13.4.5 Solar Radiation Shield Installation ...................................................................13-5 13.4.6 Connections.....................................................................................................13-6

13.5 Indicators – PDB-1 .....................................................................................................13-7 13.5.1 Operational Range...........................................................................................13-7

13.6 Precision Digital Barometer PDB-1 Specifications .....................................................13-7 13.6.1 Temperature Range.........................................................................................13-7 13.6.2 Pressure Range...............................................................................................13-7 13.6.3 Pressure Measurements..................................................................................13-7 13.6.4 Optional Temperature Sensor .........................................................................13-7 13.6.5 Communications ..............................................................................................13-8 13.6.6 Backup Battery ................................................................................................13-8

LIST OF ILLUSTRATIONS

Figure 1-1: IMS-1500C Antenna ...............................................................................................1-8 Figure 1-2: IMS-1500C Equipment Rack Assembly .................................................................1-9 Figure 1-3: IMS-1500C System Computer Assembly .............................................................1-10 Figure 2-1: Opening Screen......................................................................................................2-2 Figure 2-2: Main Flight Screen..................................................................................................2-3 Figure 2-3: Sonde Parameters..................................................................................................2-4 Figure 2-4: Calibration File(s) ...................................................................................................2-4 Figure 2-5: Preflight Data Entry ................................................................................................2-5 Figure 2-6: Flight Ready .........................................................................................................2-10 Figure 2-7: Flight Train............................................................................................................2-17 Figure 2-8: Regulator Rigging Diagram ..................................................................................2-19 Figure 2-9: Unwinder ..............................................................................................................2-19 Figure 2-10: VIZ B2 Radiosonde ............................................................................................2-24


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Figure 2-11: Radiosonde with Sleeve Removed.....................................................................2-26 Figure 2-12: Radiosonde Foam Box ........................................................................................2-27 Figure 2-13: Hygristor and Clips .............................................................................................2-28 Figure 2-14: Radiosonde Temperature Arm ...........................................................................2-30 Figure 2-15: Radiosonde with Battery Installed ......................................................................2-31 Figure 2-16: TEMP-1 ..............................................................................................................2-42 Figure 2-17: TEMP-2 ..............................................................................................................2-42 Figure 3-1: Flight Screen ..........................................................................................................3-3 Figure 3-2: Receiver Area.........................................................................................................3-6 Figure 3-3: Radiosonde Area....................................................................................................3-7 Figure 3-4: Telemetry Area .......................................................................................................3-7 Figure 3-5: PTU Graph ...........................................................................................................3-10 Figure 3-6: Wind Graph ..........................................................................................................3-11 Figure 3-7: T/Log P Graph ......................................................................................................3-12 Figure 3-8: Report Generation ................................................................................................3-13 Figure 3-9: Standard Levels....................................................................................................3-14 Figure 3-10: Significant Levels................................................................................................3-14 Figure 3-11: Physical Values Report ......................................................................................3-15 Figure 3-12: View Physical Values .........................................................................................3-16 Figure 3-13: Simulated Flight..................................................................................................3-18 Figure 4-1: Utilities ....................................................................................................................4-1 Figure 4-2: Create Archive........................................................................................................4-2 Figure 4-3: Restore from Archive..............................................................................................4-3 Figure 4-4: Deleting Old Files ...................................................................................................4-4 Figure 4-5: Enable Software Function ......................................................................................4-4 Figure 5-1: System Setup .........................................................................................................5-1 Figure 5-2: Comm Ports Parameter..........................................................................................5-2 Figure 5-3: Color Parameters ...................................................................................................5-2 Figure 5-4: System Parameters 1 .............................................................................................5-3 Figure 5-5: System Parameters 2 .............................................................................................5-5 Figure 5-6: NWS Parameters....................................................................................................5-6 Figure 5-7: WMO Reports Selection .........................................................................................5-7 Figure 5-8: WMO Coding Parameters 1 ...................................................................................5-8 Figure 5-9: WMO Coding Parameters 2 ...................................................................................5-9 Figure 6-1: CDU Keyboard .......................................................................................................6-1 Figure 7-1: Sounding taken inside a thunderstorm with very erratic temperature data. ...........7-3 Figure 9-1: Cylinders Secured in Group ...................................................................................9-2 Figure 9-2: Cylinders Secured in Pairs .....................................................................................9-3 Figure 10-1: Pressure Profile Indicating Fluctuations .............................................................10-1 Figure 10-2: Pressure Plot with Processed Data Indicating Slowing of Ascent at Base of Wave

Beginning at Minute 9.......................................................................................................10-2 Figure 10-3: Pressure Waves at Minutes 43 and 51 with processed Data Indicating Temporary

Negative Ascent Rates .....................................................................................................10-3 Figure 10-4: Temperature and RH Plot Showing Erratic Data................................................10-4 Figure 10-5: Temperature Plot Indicating Erratic Data 25 to 41 Minutes................................10-5 Figure 10-6: Temperature Plot with Erratic Data from 85 to 90 Minutes.................................10-5 Figure 10-7: TTDD Message with Abrupt Temperature Shift..................................................10-6 Figure 10-8: WMO Levels Showing Unrealistic Temperature Change Over 80 Meters..........10-6 Figure 10-9: Wind Plot Showing 24 Knot Wind Speed Change from Minute 78 to 80 and

Direction Change of 75 Degrees from Minute 77 to 79 ....................................................10-7 Figure 10-10: Winds Above 100 hPa Indicate 24 Knot Speed Change from Height 77 to 79 10-7


Table of Contents xii June 2009 Revision B

Figure 10-11: Data Dropout Illustrated by Dewpoint Dropout .................................................10-8 Figure 10-12: Expanded View of Dewpoint Dropout...............................................................10-8 Figure 10-13: Processed Data with Dropouts in Dewpoint and Height Data ..........................10-9 Figure 10-14: TTBB Message with Levels Showing Dewpoint Depression Dropout ..............10-9 Figure 10-15: Marked Data Prior to Applying User Edits ......................................................10-10 Figure 10-16: Marked Data After Applying User Edits ..........................................................10-10 Figure 10-17: TTBB Message after Applying User Edits Levels with 00 Dewpoint Depression

Gone...............................................................................................................................10-11 Figure 10-18: Relative Humidity Indicates Unrealistic Drying Immediately Off Surface........10-11 Figure 10-19: Processed Data and Relative Humidity Plot Before Marking Data.................10-12 Figure 10-20: Processed Data and Relative Humidity Plot After Marking Data....................10-12 Figure 10-21: Relative Humidity Standard Indicates Extremely Dry Layers near Surface....10-13 Figure 10-22: Chilled Mirror RH Readings Below 10%.........................................................10-14 Figure 10-23: Dry Slots from 13 to 40 Minutes and above 75 Minutes.................................10-15 Figure 10-24: Processed and Raw Data for Flight with Late Release Detection ..................10-16 Figure 10-25: WMO Levels and Pressure Plot for Flight with Late Release Detection.........10-17 Figure 10-26: Temperature Sensor Failure Display..............................................................10-17 Figure 10-27: Leaking Pressure Cell Causing Unrealistic Height and Pressure Values.......10-18 Figure 10-28: Wetbulb Effect or Evaporative Cooling Before Applying User Edits ...............10-19 Figure 10-29: Wetbulb Effect Eliminated After Marking Temperature Data..........................10-20 Figure 10-30: Expanded Temperature Plot at Termination...................................................10-21 Figure 10-31: Expanded Pressure Plot at Termination.........................................................10-21 Figure 10-32: Processed Data with GPH Heights.................................................................10-22 Figure 10-33: Pressure Increase since Baseline and Not Updated in Surface Observation 10-22 Figure 12-1: Temp-1 ...............................................................................................................12-9 Figure 12-2: Temp-2 ...............................................................................................................12-9 Figure 13-1: Precision Digital Barometer ................................................................................13-1 Figure 13-2: Optional Temperature Sensor Radiation Shield .................................................13-3 Figure 13-313: Removing the Barometer Box Lid...................................................................13-4 Figure 13-4: Mounting the Barometer Box to the Rack Mount Plate ......................................13-5 Figure 13-5: Position of the U-bolt used to mount the Solar Radiation Shield........................13-6 Figure 13-6: PDB-1 Connections ............................................................................................13-6

LIST OF TABLES

Table 1-1: List of CHUAS Sites.................................................................................................1-2 Table 1-2: System Computer ..................................................................................................1-11 Table 2-1: PreFlight Data Entry ................................................................................................2-6 Table 2-2: Pressure Correction.................................................................................................2-8 Table 2-3: Termination Due to Missing Temperature Data......................................................2-37 Table 2-4: Deadlines for Transmitting Upper-air Data ............................................................2-41 Table 2-5: Standard Atmosphere Heights...............................................................................2-49 Table 2-6: Altitude of the Fixed Wind Levels ..........................................................................2-49 Table 2-7: Stability Index ........................................................................................................2-51 Table 3-1: iMetOS Processed Log File Column Definitions......................................................3-2 Table 6-1: Direction Controls ....................................................................................................6-3 Table 6-2: CDU Error Messages.............................................................................................6-12 Table 11-1: Amount of Low/Middle Cloud, Nh ........................................................................11-2 Table 11-2: Coding of Low Cloud, CL .....................................................................................11-2


Revision B June 2009 xiii Table of Contents

Table 11-3: Height of Cloud Base above Ground, h ...............................................................11-3 Table 11-4: Coding of Middle Cloud, CM ................................................................................11-4 Table 11-5: Coding of High Cloud, CH....................................................................................11-5 Table 11-6: Coding of Present Weather, WW.........................................................................11-5 Table 12-1: Station Number & Call Sign ...............................................................................12-11

TABLE OF ABREVIATIONS

ABV Mandatory and Significant Levels Above 100 hPa AC Alternating Current AF Audio Frequency AFC Automatic Frequency Control AFTN Aeronautical Fixed Telecommunications Network AGL Above Ground Level ALC Automatic Level Control AM Amplitude Modulation Auto Automatic AWIPS Advance Weather Interactive Processing System (US NWS) AZ Azimuth BIT Built In Test BMD Begin Missing Data C Centigrade CCW Counterclockwise CD Compact Disk CDROM Compact Disk Read Only Memory CDU Control Display Unit CPU Central Processing Unit cm centimeters CW Clockwise dBm Decibels relative to 1 milliwatt DC Direct Current Deg Degree DOC Department of Commerce (US) DSP Digital Signal Processor EEPROM Electrically Erasable Programmable Read Only Memory EL Elevation EMD End Missing Data ENT Enter EPROM Erasable Programmable Read Only Memory Err Error FDD Floppy Disk Drive Freq Frequency ft Feet FTP File Transfer Protocol gm Gram GTS Global Telecommunications System hPa Hectopascal


Table of Contents xiv June 2009 Revision B

IF Intermediate Frequency IP Internet Protocol IMS International Met Systems ISCS International Satellite Communications System ITU International Telecommunication Union km Kilometer kt Knot (nautical miles per hour) LOS Loss of Signal LRU Line Replaceable Unit m Meters Man Manual MAN Mandatory Levels to 100 hPa max Maximum MCU Motion Control Unit mb Millibar MHz Megahertz min Minimum Min Minute mph Miles Per Hour MSL Mean Sea Level NCDC National Climatic Data Center (US) NCEP National Centers for Environmental Prediction (US) NLSC National Logistics Support Center (US) NOAA National Oceanic and Atmospheric Administration (US, DOC) NWS National Weather Service (US) NWSTG National Weather Service Telecommunications Gateway PTU Pressure, Temperature and Humidity QC Quality Control RAM Random Access Memory RDF Radiotheodolite Direction Finder REC Receiver Rel Relative RF Radio Frequency RH Relative Humidity RMTN Region IV Meteorological Telecommunications Network ROM Read Only Memory SCA System Communication Assembly SCU System Control Unit SDC Sonde Data Converter SGL Significant Levels to 100 hPa SID Station Identifier Sig Signal SIM System Integration Manager SMC System Meteorological Computer Sonde Radiosonde SPS Signal Processing System SYS System TPC Tropical Prediction Center (National Hurricane Center) UHF Ultra High Frequency (radio) UPS Uninterruptible Power Supply UTC Universal Time Coordinated


Revision B June 2009 xv Table of Contents

UTM Universal Transverse Mercator V Volt VAD Velocity Azimuth Display VLF Very Low Frequency VSAT Very Small Aperture Terminal WMO World Meteorological Organization


Revision B June 2009 1-1 SMC OPS

CHAPTER 1 IMS-1500C SYSTEM METEOROLOGICAL COMPUTER OPERATION

1.1 Introduction The National Weather Service (NWS) supports ten upper air stations in the Cooperative hurricane Upper-Air Stations (CHUAS) network in the Caribbean. These observations are vital to forecast and warnings of the Tropical Prediction Center for the prediction of hurricanes. The CHUAS stations include Bahamas, Barbados, Belize, Curacao, Dominican Republic, Grand Cayman, Jamaica, San Andres Island, St. Maarten, and Trinidad. All aspects of the rawinsonde observation are covered from preparing the radiosonde and flight train to processing and disseminating upper-air data. Since operations at each upper-air station in the CHUAS network can vary, sections to this handbook have been included that may or may not pertain to each office. (See chapter 12 for Quick Guide for Radiosonde Flights). The handbook does not provide detailed procedures for taking upper-air-observations with other NAVAID rawinsondes or with radio-direction finding (RDF) equipment other than the IMS-1500C Meteorological Tracking Station. The IMS-1500 System Meteorological Computer (SMC) is, in principle, the station operator position, enabling control of IMS-1500 RDF and Sippican Mark II radiosonde decoder functions, recording and processing of data transmitted by the radiosonde and the RDF, and generation of operator-selected meteorological data, messages and graphs in real time during and/or after flight. An additional function of the IMS-1500 SMC is playback of flights from previously recorded raw data files. This Manual describes the characteristics and operating procedures for using the IMS-1500C and iMetOS version 4.00.27. Included is information on the following topics:

CHAPTER 1 – IMS -1500c System Meteorological Computer (SMC) Operation CHAPTER 2 – Flight Operations CHAPTER 3 – InterMet Meteorological Operating System (iMetOS) CHAPTER 4 – SMC Utilities CHAPTER 5 – SMC Setup CHAPTER 6 – CDU Operations CHAPTER 7 – Quality Control of Data CHAPTER 8 – Completion of Documentation (Forms) CHAPTER 9 – Station Safety CHAPTER 10 – Special In-flight Situations CHAPTER 11 – Clouds and Weather Codes CHAPTER 12 – Communications Architecture and Rawinsonde Quick Guide CHAPTER 13 – Precision Digital Barometer

1.1.1 Observational Procedures The procedures and operational requirements defined in this handbook apply only to CHUAS upper-air stations. These procedures have been written to ensure NWS compliance with the observational standards defined in Federal Meteorological Handbook Number 3 and the World


SMC OPS 1-2 June 2009 Revision B

Meteorological Organization (WMO) Code Manual 306 Volume I and II.

1.1.1.1 Times of Observations

Observations from the CHUAS stations shall be made once daily, 1200 UTC, unless extenuating and justifiable circumstances prevent it. Following coordination with NCEP’s Tropical Prediction Center, or as directed by local authority, most sites will fly two flights per day during the hurricane season at 0000 and 1200 UTC, see Table 1-1. Actual release times for the 00 and 12 UTC standard scheduled upper air observations shall be as close as possible to H–60 minutes, where H is one of the standard times. The release time for a synoptic observation shall not fall outside the time range from H–60 to H+60, a period known as the release window. For all non-standard observation times, the release window, in regard to the record time of the observation, is from 30 minutes before to 29 minutes after the hour of assigned observation time.

Table 1-1: List of CHUAS Sites

Station Equipment Type

Observation Remarks

00Z 12Z Bridgetown, Barbados IMS-1500C No Yes * Curacao, Netherlands Antilles IMS-1500C No Yes ** Grand Cayman, Cayman Islands IMS-1500C No Yes *** Kingston, Jamaica IMS-1500C No Yes * Ladyville, Belize IMS-1500C No Yes * Nassau, Bahamas IMS-1500C No Yes Piarco, Trinidad IMS-1500C No Yes ** San Andres island, Colombia IMS-1500C No Yes Santo Domingo, Dominican Republic IMS-1500C No Yes ** St. Maarten, Netherlands Antilles IMS-1500C No Yes ** Note: * Takes 00 Z observation mid June through mid October ** Takes 00 Z observation end of July through mid October *** Takes 00 Z observation 1 June through 21 November

1.1.1.2 Transmission of Observations

The coded message containing data from the observation shall be provided to the telecommunication system for dissemination to government agencies and other data users in as timely a manner as possible. The deadlines for transmitting the coded messages are provided in Chapter 8, Table 8-1.

1.1.1.3 Recording and Preserving Observations

An archive record of all synoptic rawinsonde observations shall be made for submission to the National Climatic Data Center (NCDC). The requirements for recording and disseminating these records to the NCDC are described in Chapter 12.3 and sub-sections. An archive record shall also be made of unscheduled observations that are transmitted over telecommunications for use by the government or other data users. The procedures for archiving the flight are section 2.29 and 2.30.

1.1.1.4 CHUAS Meteorological Station Information

CHUAS Meteorological stations may be identified in several ways:



1. A station index number, assigned by the World Meteorological Organization (WMO). They are used for international weather data exchange and station documentation and are available in WMO Manual on Codes, WMO No. 306. The station index number is composed of the block number (II) and the station number (iii).

2. A location indicator, assigned by the International Civil Aviation Administration (ICAO). A current list of ICAO (4-letter) location indicators is found in the ICAO publication “Location Indicators” (7910).

3. The station index numbers have been allocated for CHUAS as follows:

a. WMO Index Number

b. ICAO Location Indicator

c. Station Name

d. Station Country

e. WMO Region – The LAT/LON position for the baseline of the radiosonde. The LAT/LON positions are in degrees and decimals.

f. Station Position for the baseline of the radiosonde

g. Station Elevation (MSL) – Height of the PDB or other pressure indicator for baseline of the radiosonde.

h. Upper Air Position – The LAT/LON for the normal release point of the radiosonde.

i. Upper Air Elevation – Height for the release point of the Radiosonde. The floor of the inflation building plus 1.2 meters. (Approximates the point where the radiosonde is typically released.)

WMO Index Number: 78073 ICAO Location Indicator: MYNN Station Name: Nassau Airport Country: Bahamas WMO Region: 4 Station Position: (dms) 25-03-00N 077-28-00W Station Elevation (Ha): 2 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

25-03-00N 25.0500N

077-28-00W 77.4600W

Upper Air Elevation (Hp): 2 Meters



WMO Index Number: 78384 ICAO Location Indicator: MWCR Station Name: Owen Roberts Airport Grand Cayman Country: Cayman Islands WMO Region: 4 Station Position: (dms) 19-17-.38.4N 081-21-46.7W Station Elevation (Ha): 3 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

19-17.38.5N 19.294028N

081-21.47.1W 81.363083W


WMO Index Number: 78397 GUAN Station ICAO Location Indicator: MKJP Station Name: Kingston / Norman Manley Country: Jamaica WMO Region: 4 Station Position: (dms) 17-56-00N 076-47-00W Station Elevation (Ha): 2 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

17-56-00N 19.9391N

076-47-00W 76.7868W


WMO Index Number: 78486 ICAO Location Indicator MDSD Station Name: Santo Domingo Country: Dominican Republic WMO Region: 4 Station Position: (dms) 18-26-00N 069-53-00W Station Elevation (Ha): 14 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

18-28-00N 18.4666N

069-53-00W 69.8833W




WMO Index Number 78583 GUAN Station ICAO Location Indicator: MZBZ Station Name: Belize / Phillip Goldston Intl. Airport Country: Belize WMO Region: 4 Station Position: (dms) 17-32-00N 088-18-00W Station Elevation (Ha): 5 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

17-32-00N 17.5333N

088-18-00W 88.3000W


WMO Index Number: 78866 ICAO Location Indicator: TNCM Station Name: Juliana Airport, St. Maarten Country: Netherlands Antilles WMO Region: 4 Station Position: (dms) 18-03-00-N 063-07-00W Station Elevation (Ha): 3 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

18-03-00N 18.0423N

063-07-00W 63.1090W


WMO Index Number: 78954 (GUAN Station) ICAO Location Indicator: TBPB Station Name: Grantley Adams Country: Barbados WMO Region: 4 Station Position: (dms) 13-04-00N 059-29-00W Station Elevation (Ha): 47 Meters Upper Air Position: (dms): Preflight data entry: (Decimals)

13-04-00N 13.0600N

059-30-00W 59.5000W




WMO Index Number: 78970 ICAO Location Indicator: TTPP Station Name: Piarco International Airport, Trinidad Country: Trinidad and Tobago WMO Region: 4 Station Position: (dms) 10-37-00N 061-21-00W Station Elevation (Ha): 15 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

10-35-00N 10.5800N

061-21-00W 61.3500W


WMO Index Number: 78988 GUAN Station ICAO Location Indicator: TNCC Station Name: Hato Airport, Curacao Country: Netherlands Antilles WMO Region: 4 Station Position: (dms) 12-12-00N 068-58-00W Station Elevation (Ha): 54 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

12-12-00N 12.2000N

068-58-00W 68.9594W


WMO Index Number: 80001 ICAO Location Indicator: SKSP Station Name: San Andres Island Country: Colombia WMO Region: 4 Station Position: (dms) 12.35.17.7N 081.42.04.2W Station Elevation (Ha): 2 Meters Upper Air Position: (dms) Preflight data entry: (Decimals)

12.35.17.7N 12.58825

081.42.03.8W -081.701056




1.1.2 IMS-1500C Functional Overview The IMS-1500C is a lightweight, portable Radiotheodolite system designed for automatic, real-time tracking and data processing of radiosonde data from launch until termination of the flight as the radiosonde is carried into the upper atmosphere by an aerological sounding balloon. The antenna receives meteorological data transmitted over the 1680 MHz band from the radiosonde, at a rate determined by the particular radiosonde, and sends the received data to the Signal Processing System (SPS) as a baseband signal. The SPS performs the required decoding of the received signal in order to recover the meteorological (and, depending on the radiosonde being used, the GPS data) measured by the sensors in the Radiosonde. Note that radiosondes from different manufacturers, including different models from the same manufacturer, may require a different SPS. The SPS uses this data to compute atmospheric pressure, temperature, humidity and wind at the radiosonde approximately once every second as it is carried up through the atmosphere. The SPS sends the computed results to the System Computer, which produces standardized weather data products. The IMS-1500C system is capable of operating with several radiosondes and SPSs. Sippican B2 Radiosondes were initial deployed and are still being used. However, the iMetOS software is designed to allow multiple radiosondes to be used. The Station Data Display has a field titled “Radiosonde Type” and from the drop-down menu other radiosonde types may be selected. This entry is made once and only has to be changed if there is a change in the type of radiosonde being used. The software automatically displays the proper screens for the type of radiosonde selected. The Antenna is an integrated electromechanical system that uses microprocessors and software to the greatest extent possible to manage the system's operations. It works on the principle of an automatic Radiotheodolite. A parabolic dish reflector and the Antenna are mounted on a movable frame to allow for both azimuth and elevation movements. By measuring and adjusting for azimuth and elevation errors between the line-of-sight to the radiosonde and the antenna boresight, the antenna is able to track a moving radiosonde to a great distance. Servomotors under the control of the Motion Control Unit (MCU) control these movements. All electronic and mechanical elements required for acquiring the transmitted signal and maintaining the orientation of the Antenna are contained in the Antenna Assembly. Antenna functions can be controlled by the System Computer or by the CDU included with the Antenna.

1.1.2.1 Equipment Overview

The IMS-1500 consists of an Antenna, an Equipment Rack, and a System Computer. The Antenna portion is shown in Figure 1-1; the Equipment Rack is shown in Figure 1-2; and the System Computer is shown in Figure 1-3.



1

2

3

4

5

6

7

8

Figure 1-1: IMS-1500C Antenna

The Antenna (Figure 1-1) consists of: − Tripod Unit (1) − Azimuth Unit (2) − Alignment Unit (3) − Elevation Unit (4) − Dish Unit (5)



− CDU (6) − Cables

• Antenna Power Cable (7) • Antenna Data Cable (8) • CDU Cable (part of item 6)

EVENTRESET BASE BAND

POWER

GJ1

SIGNAL

GJ2

APC

0

Figure 1-2: IMS-1500C Equipment Rack Assembly The Equipment Rack (Figure 1-2) consists of:

− Power Supply (1) − Data Converter with its 17 VAC Power Supply (2) − Signal Processing System (SPS (3) − Uninterruptible Power Supply (UPS) (4)

1.1.2.1.1 Utility Power to the UPS

Utility power must be applied to the UPS at all times to maintain a full charge on the UPS batteries. When the system is turned on, power is provided to the complete system (Antenna,

1

2

3

4



System Computer and Equipment Rack) by the utility power unless there is a utility power failure. If there is a utility power failure, power is provided to the system by the UPS batteries for up to one hour.

1 2 3 475 6 8 9

10

11

12

Figure 1-3: IMS-1500C System Computer Assembly

The System Computer (Figure 1-3) is a personal computer (PC) consisting of:

− Central Processing Unit (CPU) (1) − Power supply (2) − Hard drive (3) − RAM (4) − CDROM (5) − 3.5” Floppy disk drive (FDD) (6) − 5.25” Floppy disk drive (FDD) (7) − Modem (8) − Keyboard (9) − Mouse (10) − Printer (11) − Monitor (12) − Cables

• Data Converter to COM1 • SPS to COM2 • Computer to Printer • UPS to Computer power cable



1.1.2.2 System Computer

The System Computer consists of a chassis, a mouse, a monitor, a keyboard and a printer. The chassis consists of a CPU, hard drive, ROM, power supply, CDROM, modem and both a 3.5” and 5.25” floppy disk drives (FDD). The System Computer is commercial available personal computer (PC) running software that provides data processing, data archiving, data dissemination, and automated and manual system control functions. The System Computer controls and monitors all parts of the system and provides output data in standard WMO format. The hardware characteristics are listed in Table 1-2.

Table 1-2: System Computer

Item Minimum Requirement CPU 32 bit processor, Intel Pentium IV 2.00 GHz Operating System Windows 98 or newer version RAM 256 MB Hard Disk 40 GB Cache memory 512 KB FDD 3.5 inch FDD 5.25 inch CDROM drive 48x Display 17 inch Graphics Intel Accelerated 3D graphics with 32 MB RAM Keyboard PS2 Printer HP DeskJet color Ports Four serial, one parallel Mouse PS2 Modem 56K telephone modem Ethernet Intel 10/100 Ethernet adaptor CDs Provide all software on CDs

1.1.2.3 System Software

After all the aforementioned system tasks have been managed, the processing of raw data into data usable by the weather agencies is performed in the System Computer. The System Computer functions are:

− Menu driven − Have provisions for floppy disk entry of baroswitch and thermistor calibration data during

preflight preparation − Provide improved estimates of the true data by filtering and interpolation of raw

measurements for short periods of missing data using previous and later measurements − Have provisions for changes in the thermistor and hygristor formula/constants when

required − Provide for processing of the radiosonde and wind data for printout in standard WMO

format for standard levels, significant levels, tropopause, freezing level, wind singularities, etc., including creating temporary and pilot messages in standard WMO format

− Provide the capability to transmit the coded data from the System Computer via a suitable interface to a central system such as a dial-up modem



− Have provisions for launch control and system status checks prior to launch − Operate with Microsoft Windows operating system − Be written using recent 32 bit C++ software development system − Have data acquisition and data processing functions − Accept surface data manually − Accept inputs of radiosonde data and angle data − Compute real time meteorological values, including wind speed and direction in real time

with graphical and numerical data available within 5 minutes after launch − Perform data quality checks from pre-defined criteria − Archive data and save in storage media − Provide real time graphics of sounding with tracking and meteorological data display,

including the health of the ground equipment − Display real time data in user selectable units − Process met data to produce significant level points, including max/min temperatures,

max/min humidities, freezing level, tropopause, last level reached and balloon burst – store data for generation of reports and messages for transmission to network through the modem

− Produce reports of standard and significant levels which includes geopotential heights, time, elapsed time, temperature, pressure, relative humidity, dew point depression, wind speed and direction

− Generate TEMP (A/B/C/D) and PILOT messages for transmission in WMO format. − Prepare a table of PTU data in ASCII text format once every minute − Apply data quality checks based on pre-defined threshold values − Provide visible and audible warnings for errors − Have provisions for launch control and system status checks prior to launch − Execution of a simulated flight using data from any previous flight − Make provisions for generating the following diagrams:

• A Stuve thermodynamic diagram • A Skew-T log-P thermodynamic diagram • Plots of temperature, dew point • Plots of pressure versus temperature, geopotential height and humidity • Plots of time versus temperature, pressure, humidity, geopotential height • Wind speed and direction


Revision B June 2009 2-1 Flight OPS

CHAPTER 2 FLIGHT OPERATIONS

2.1 Launch Sequence PreFlight operations must be performed before a flight can be successfully launched. There are six basic steps required:

1. Activate the iMet-1500C System Computer

2. Activate the Sippican B2 Radiosonde

3. Activate and initialize the iMetOS meteorological software

4. Complete the pre-flight baseline data entry and radiosonde check

5. Inflate the met balloon and prepare the flight train

6. Confirm operational status of all systems and release the balloon

2.1.1 Activate the iMet-1500C System Meteorological Computer Turn System Meteorological Computer (SMC) and monitor ON.

1. If a real flight is to be implemented, ensure the following:

a. RDF is present and connected properly, via the RS-232 data cable, to the computer

b. The SPS decoder is present and connected properly, via the RS-232 cable, to the computer. The cable from the SPS to the computer must be a null modem type cable.

c. Radiosonde is available

2.1.2 Activate the Sippican B2 Radiosonde See Paragraph 2.8.5 for Radiosonde B2 Pre-Flight Preparation

2.1.3 Activate and Initialize the iMetOS Meteorological Software Once the System Computer is on, initialize iMetOS using the desktop icon. The opening screen is a pane superimposed on the main Flight Screen.


Flight OPS 2-2 June 2009 Revision B

Figure 2-1: Opening Screen

The opening screen pane shows the following two options

1. Real Flight

2. Simulated Flight

2.1.3.1 Frequency Lock-On

After the radiosonde is activated the UHF receiver will automatically scan the 1680 MHz band, tune to the strongest frequency and activate the Automatic Frequency Control (AFC) to remain locked onto the signal. Once the signal is acquired, the frequency and signal strength will be displayed as a yellow bar on the Receiver frame of the Main Flight Screen (see Figure 2-2)

NOTE

The AFC must be switched OFF before automatic or manual frequency search can be executed.



Figure 2-2: Main Flight Screen

If no signal is indicated on the Receiver frame and no PTU readings appear, this may indicate that there is a problem with the radiosonde or the UPS. Verify that the radiosonde is on and the receiver is properly tuned by clicking the Frequency Search button. When the receiver is correctly tuned, the signal strength graph will show the signal to be greater than - 70 dBm (actual strength will depend on the distance between the radiosonde and the antenna).

2.1.3.2 File Name Entry

To initialize the flight data record, select New from the File menu on the Flight Screen menu bar, or from the Flight Screen toolbar. Go to File → “New” Radiosonde Parameters appears. (See Figure 2-3. Hit the “…..” button and load the B2 proper calibration file name from the listed directory (See Figure 2-4). It is important that the calibration number and the calibration file name match. The SPS will not start a flight if the data is not matched up appropriately. Once this is complete, the Preflight data entry Screen (See Figure 2-5) will automatically be displayed for entry of preflight data for this flight. Verify that the receiver is picking up the radiosonde signal by pressing the Freq Search button (alternatively, press FreqUp and FreqDown buttons on Flight Screen to tune receiver frequency up and down respectively). If the receiver is not picking up the radiosonde signal, the words NO DATA will appear in left portion of status bar. If the receiver is picking up the radiosonde signal, pressure, temperature and humidity readings appear in their proper place on Flight Screen in



about a minute. (These records initially refer to meteorological conditions on the ground.) If the words NO DATA appear, or if no PTU readings appear, this may indicate that there is a problem with either the radiosonde or the SPS. In most cases, resetting the SPS solves many problems. To reset the SPS, press the RESET SPS button on the iMetOS window. On occasion, the communications cables connected to the computer, the SPS, and the Data Converter become loose. Check that these cables are properly secured. If PTU data still does not appear, start the process again by restarting the software and selecting another radiosonde.

Figure 2-3: Sonde Parameters

Figure 2-4: Calibration File(s)

2.1.4 PreFlight Data Entry and Radiosonde Status Check

2.1.4.1 PreFlight Data Entry



Figure 2-5: Preflight Data Entry

PreFlight data entry is required for a baseline reference. To establish this baseline, meteorological data is entered into the Surface Data frame of the PreFlight Data Entry window. Surface data must be entered for the PreFlight process to be completed. Station Data items will be those of the previous flight. Flight Date and Time are entered automatically from the system PC. The Sonde ID is entered automatically from the radiosonde data stream.

NOTE: Do not press the Save button on the Preflight Data Entry screen until the

Radiosonde Status Check has been completed.

The Preflight data entry screen Table 2-1 is provided for all CHUAS to ensure the data is readily available for rawinsonde operators. The operators should check the station data before entering the surface observation.



Table 2-1: PreFlight Data Entry

Site Name Station Code

Station Name

Latitude “N” DD/MM’SS.s Decimals

Longitude “W”DD/MM/SS.s Decimals

Release Pt. Pressure Correction

Bahamas 78073 MYNN 25.03.10.326.125.052868

77.24.41.9 77.411639 2 0

Barbados 78954 TBPB 13.04.17.9 13.071639

59.29.31.3 59.492028 47 0

Belize 78583 MZBZ 17.32.02.4 17.534

88.16.46.9 88.279694 5 +.6

Curacao 78988 TNCC 12.10.47.6 12.179889

68.57.33.7 68.959361

54

0

Dominican Republic 78486 MDSD 18.28.27.9

18.474417 69..52.12.6 69.870167

14

0

Grand Cayman 78384 MWCR 19.17.19.7

19.294028 81.22.04.9 81.363083 3 0

Jamaica 78397 MKJP 17.56.20.6 17.939056

76.46.51.2 76.780889 2 0

San Andres 80001 SKSP 12.35.17.8 12.58825

81.42.03.8 81.701056 2 0

St. Maarten 78866 TNCM 18.02.32.1 18.04225

63.06.32.7 63.109083

3

0

Trinidad 78970 TTPP 10.36.36.0 10.6100

61.20.49.3 61.347028 15 0

If the flight to be launched is the first flight for this location, station data items on preflight data entry screen will be those of the previous location; if previous flights have been launched in this location, station data items on preflight data entry screen will be those of the previous flight. Enter surface data (based on accurate external measuring devices) and station data relative to this location or flight. Use the Tab key to move from field to field. PreFlight data entry is required for a baseline reference. To establish this baseline, meteorological data is entered into the PreFlight Data Entry window. All values should be entered manually in the right column of the Surface Data frame along with the Cloud code and Wx Code (see section A below). Detailed instruction can be found in Chapter 11. Correct cloud data is imperative. It directly influences the Radiation Correction performed by NCEP. The Station Data entries may be entered by the site administrator or the operators. Any changes other than the Surface Observation must be coordinated with site administrator. Compare pressure reading of external measuring device (if available) with pressure reading appearing on Flight Screen. If pressure offset is > ±5 mB, start process again with another radiosonde.



A. Surface Data

1. Pressure – Station pressure shall be taken to the nearest tenth of a Hectopascal (hPa), and corrected for the appropriate pressure at the release point (see Station Elevation Data below)

2. Temperature – Record the dry bulb temperature to the nearest tenth of a degree Celsius

3. Humidity – Record the humidity to the nearest tenth of a percent

4. Wind Direction – Enter to the nearest tenth of a degree. For calm winds, estimate a direction or use 360 degrees.

5. Wind Speed – Enter to the nearest tenth of a knot. For calm winds, a single “0” can be entered for wind speed.

6. Cloud Code – Enter the five digit code NhCLhCMCH

7. Weather (WX) Code – Enter the four digit code WWWW

NhCLhCMCHWWWW

Nh - Amount of sky covered in oktas (eighths) by low clouds, or if no low clouds are present, coverage by middle clouds CL - Type of low cloud h - Height of the lowest cloud base CM - Type of middle cloud CH - Type of high cloud

WWWW - Present weather coded in two groups of WW. Enter the two code groups from Table 16-6 (with highest numerical priority) that best represents the site’s weather. (Note that some code groups refer to weather during the previous hour but not at the time of observation.) The code with the highest priority should appear first. If only one WW group is applicable to the present weather, then use that code twice.

B. Station Data

1. Station Code – Five digit WMO Station Index (i.e., 78583)

2. Station Name – Four digit ICAO Location Indicator (i.e., MZBZ)

C. Launch Location - release point of the balloon and radiosonde

1. Latitude 17. 53390 N (Decimals)

2. Longitude 88.31303 W (Decimals)

3. Altitude 5.0 m (meters)

D. Flight Date and Time – Flight Date and Time are entered automatically from the system PC

E. Sonde ID – The Sonde ID is entered automatically from the radiosonde baseline.

F. PTU Ground Check – Each column contains the most recent readings for sonde Pressure, Temperature and Humidity. The data field at the bottom of each column calculates the difference between the most recent sonde reading and the Surface Data.



G. Ascension Info:

1. Ascension No – The first release on/or after January 1 of each year will be numbered 001

2. Release No – Default to 1 (2 for second releases), etc.

H. Station Elevation Data:

1. Station Elevation – Barometer Height (m MSL). Height of the barometer and baseline point should be the same.

2. Release Point Pressure Correction (hPa) - Derived by finding the difference of elevation at the Station Elevation for baseline point and the radiosonde release point.

a. The correction will be added if the release point height is lower than the baseline height and subtracted if the release point height is higher than the baseline height.

b. The Release point height is the height of the inflation building’s floor in meters + 1.2 meters. (Approximates the point where the instrument is typically released.) Use Table 2-2 to find the pressure correction.

Table 2-2: Pressure Correction Pressure Correction in hPa Applied to Radiosonde Baseline Station Pressure

Barometer Elevation in Meters Mean Sea Level Barometer Height Minus Release Point Height (m)

-5 to 299.4 299.5-599.4 599.5-899.4 899.5-1199.4 1199.5-1499.4 1499.5-1799.4 1799.5-2199.4

0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 3 0.4 0.3 0.3 0.3 0.3 0.3 0.3 4 0.5 0.5 0.4 0.4 0.4 0.4 0.4 5 0.6 0.6 0.6 0.6 0.5 0.5 0.5 6 0.7 0.7 0.7 0.7 0.6 0.6 0.6 7 0.8 0.8 0.8 0.8 0.7 0.7 0.7 8 0.9 0.9 0.9 0.9 0.8 0.8 0.8 9 1.1 1.1 1.0 1.0 1.0 0.9 0.9

10 1.2 1.2 1.1 1.1 1.1 1.0 1.0 11 1.3 1.3 1.2 1.2 1.2 1.1 1.1 12 1.4 1.4 1.3 1.3 1.3 1.2 1.2 13 1.6 1.5 1.5 1.4 1.4 1.3 1.3 14 1.7 1.6 1.6 1.5 1.5 1.4 1.4 15 1.8 1.7 1.7 1.7 1.6 1.5 1.5 26 3.1 3.0 2.9 2.8 2.7 2.7 2.6 27 3.2 3.1 3.0 2.9 2.8 2.8 2.7 28 3.3 3.2 3.1 3.0 3.0 2.9 2.8 29 3.4 3.3 3.2 3.2 3.1 3.0 2.9 30 3.6 3.5 3.4 3.3 3.2 3.1 3.0

I. When all data are complete and correct, click OK. The text FLIGHT READY will appear in the bottom status bar.



NOTE: If screen shows :Error, incomplete entry!” when OK is pressed, this means that one or more of the preflight data items were skipped; pressing OK on this error message will focus cursor on first incomplete entry. If screen shows :Error, entry out of range!” when OK is pressed, this means that one or more preflight data items were completed with a value out of range (e.g., wind direction 370°); pressing OK on this error message will focus cursor on first erroneous entry. When all entries requiring completions/correction have been completed, press OK once more.

1. Assuming that all data entries are complete and correct, screen will prompt as to whether pressure off set correction is required. (Click YES or NO as appropriate)

2. Flight screen will now appear with FLIGHT READY displayed in status bar at bottom of screen.

2.1.4.2 Radiosonde Status Check

Compare pressure reading of external measuring device with pressure reading appearing on flight screen. If pressure offset is >±5 mb, start process again with another radiosonde

2.1.4.3 PreFlight Status Check

Although the temperature and humidity sensors do not need to be recalibrated, it is necessary to verify before the flight that they have not been damaged or contaminated during storage. After Surface Data has been entered, the PTU Ground Check frame can be used to verify that the sonde’s output is within specifications. Each column contains the most recent readings for sonde Pressure, Temperature and Humidity. The data field at the bottom of each column calculates the difference between the most recent sonde reading and the Surface Data. If the absolute value of these differences is larger then 5 mb for pressure, 2º C for temperature, and 10% RH for humidity it is possible that the sonde sensors have been damaged or corrupted. If the sonde PTU is outside of allowable tolerances, check first to be sure the sonde is in close proximity to the sensors used for the PreFlight Baseline. If the sonde PTU is still outside of allowable tolerances, verify that the reference sensors are calibrated and reliable. If the sonde is acceptable, press Save on the pre-flight screen and proceed to the Baseline Data Check. If the sonde is still outside of acceptable tolerances, reject the sonde and select a new sonde. Repeat the PreFlight process by closing iMetOS and restarting the software for a Real Flight.

NOTE: At ground level, a 10 meter vertical difference between the location of the reference pressure sensor and the radiosonde can result in an error of approximately 1 mb. If the sonde is not physically located at the same altitude as the reference sensor, a height compensation factor must be included when entering the baseline pressure data.

2.1.4.4 Save PreFlight Data

When all baseline data is complete and correct, click Save. The text FLIGHT READY will appear in the bottom status bar.



Figure 2-6: Flight Ready

2.1.4.5 Radiosonde Launch Delay

If radiosonde launch has been delayed and there is reason to believe that surface data have changed significantly following preflight data entry, you can change Preflight Data before radiosonde release. The Preflight Data can not be changed after the release.

2.1.4.6 Radiosonde Second Release

The initial flight is automatically backed up to the hard drive when the flight is closed or when the operator elects to do a second release. The iMetOS will allow up to three (3) releases without changing the ascension number. The initial release will have a file extension of .001 and the second release will have file extension of .002.

2.1.4.7 Radiosonde Ready for Launch

When the radiosonde is ready for launch, the status bar indicates FLIGHT READY. It is recommended that at least ten records be received to be sure that the radiosonde is transmitting data consistently before releasing the balloon. Point the antenna in the direction the wind is expected to take the balloon and leave the antenna in the manual tracking mode until after the release. Once the radiosonde is in the air the iMetOS has automatic release detection. The observer can not start the flight. The automatic launch detection is a decrease of 4 mb after release. The flight clock will then start. The message in the bottom status bar will be replaced by the text FLIGHT IN PROGRESS. Upon sonde release, altitude, ascent rate and PTU values displayed on screen will begin to change rapidly. Wind data and slant range will appear on screen after about four minutes into the flight.



The observer must be very attentive to the IMS-1500C staying locked onto the radiosonde signal during the early stages of the flight. The azimuth and elevation Offset angles must be monitored to ensure they are less than 20.

2.2 Radiosonde The purpose of this section is to familiarize observers on the operation and handling of radiosondes. CHUAS currently uses the Sippican VIZ-B2. These radiosondes are tracked with an IMS-1500C system. Sippican has prepared step-by-step instructions for preparing their radiosonde for flight. (See paragraph 2.8.5)

2.2.1 Radiosonde Inspection The observer shall physically inspect the instrument before proceeding with an observation. The instrument shall be rejected and another instrument used if any broken, missing, discolored, or misshapen components are detected. DO NOT ATTEMPT TO REPAIR THE INSTRUMENT.

2.2.1.1 Replacement B-2 Radiosonde Calibration Files

If the calibration files for the B-2 Radiosondes as supplied on the 5 ¼ inch disk are bad or the disk drive is not working, calibration files may be obtained by email from Mr. Tom Curran Tel: (610) 397 0183 Ext. 1; Fax: (610) 397 8647; e-mail: [email protected] ) You will need to supply the serial numbers of the radiosondes. Please request these files at least a week before needing them. The calibration files should be copied into the C:\IMS\iMetOS\B2 directory.

2.2.2 Radiosonde Components Radiosondes are delivered from the National Logistics Supply Center (NLSC) to the upper-air station assembled and ready for flight. The following components make up the radiosonde instrument.

• Pressure, temperature and RH sensors measure the environment as a function of changes in sensor electrical parameters such as resistance or capacitance.

• A radio transmitter for telemetering sensor measurements to ground receivers.

• A battery for powering the electronic components.

All the electronics and some of the sensors are housed within a waterproof casing made of lightweight, durable materials. A mailing bag is included with the instrument so that it can be returned for reconditioning. Total instrument weight is approximately 500 grams. Within each box of RDF Radiosondes a floppy diskette is enclosed that contains calibration data for each radiosonde. The calibration data applies numerical constants and other calibration factors to the raw pressure, temperature, and RH data to ensure sensor accuracy.

2.2.2.1 Pressure Sensor

The Sippican (VIZ) B2 Radiosonde use a capacitance aneroid cell to measure atmospheric pressure. The cell is a metallic, wafer-shaped capsule with a partial vacuum. As the pressure changes, the cell expands (decreasing pressure) or contracts (increasing pressure), changing the separation between two plates contained inside the capsule. The pressure is determined by measuring the changing electrical capacitance between the plates. There are no springs, arms,



or contacts as was common in older pressure sensor designs. The pressure sensor is located within the instrument packaging and is not readily visible. Do not attempt to open the radiosonde to view the pressure sensor.

2.2.2.1.1 Pressure Sensor Capabilities and Limitations

The capacitive aneroid typically has an accuracy of about 0.5 hPa (with decreasing accuracy aloft), and a measuring range from 1060 to 3 hPa. It has excellent response time to rapidly changing pressures (less than a second). The capsule can occasionally leak during a flight (usually above 15 km) causing abrupt changes in pressure and consequently unrealistically high ascension rates and heights. Moreover, during radiosonde preparation, the pressure sensor may provide out of tolerance readings and shall be rejected.

2.2.2.2 Temperature Sensor

Temperature is measured on the VIZ B2 Radiosonde by the thermistor which is a small rod comprised of baked clay and iron fillings. The sensor or “thermistor” measures temperature by the change in electrical resistance across the rod caused by changing temperature. A thermistor is mounted on the end of a flexible boom outside the radiosonde package. If a thermistor is chipped, discolored, or damaged in any way, do not attempt to repair or replace the sensor. Reject the instrument and use another.

2.2.2.2.1 Temperature Sensor Capabilities and Limitations

Temperature sensors have an accuracy of about ±0.3°C in the troposphere and a very good response time to changing temperatures (generally less than 4 seconds). They are designed to operate over a temperature range of -90 to 50°C. If the thermistor is exposed to wet conditions during a flight, the “wet bulb” effect may occur causing excessive cooling in the temperature measurements. The temperature sensor is affected to some extent by long-wave (infrared or IR) and shortwave ultraviolet (solar) radiation. The effect on the data is to cause the sensor to report a different measurement than is truly representative of the atmosphere. During the daytime (i.e. when the sensor is exposed to sunshine) solar radiation is absorbed by the sensor causing it to read higher than the ambient temperature. The solar error varies with solar elevation angle with a minimum at low angles. At night, the solar effect is zero. During both day and night, the sensor radiates and absorbs long wave energy to and from its surroundings (i.e. space, ground, clouds, atmosphere, etc.) proportional to sensor temperature and the temperature of the surroundings. The long-wave error usually results in temperature readings lower than ambient but May, under some conditions, lead to a positive error. The thermistor is coated with white paint to reduce the effect of solar and infra-red radiation, but it does not adequately lessen these affects at high altitudes. At altitudes above 16 km the temperature error can exceed 1°C. Observers shall not correct or edit these data to correct for solar or the effects of infra-red radiation before dissemination. The National Center for Environmental Prediction (NCEP) and other users will apply the necessary corrections to the VIZ B2 Radiosonde.



2.2.2.3 Relative Humidity Sensor

Sippican VIZ B2 employs a “hygristor” to measure RH. The hygristor is a rectangular strip of plastic which has been dipped in a liquid mixture of carbon particles and celluloid resin and then dried. The celluloid is sensitive to RH and expands or contracts with the amount of water vapor in the air. This fluctuation caused the distance between the carbon particles to vary and thus electrical resistance across the strip. To protect the sensor from precipitation and solar radiation, the hygristor is housed within a curved, black laminated (to reduce reflected solar radiation) duct that is built into the Styrofoam Radiosonde case. The hygristor comes packed in a metallic container. During pre-flight procedures, it is removed from the container and installed into the duct. If the sensor is damaged (e.g., scratched during installation), misshapen, or discolored, select another sensor and enter the calibration data.

2.2.2.3.1 Relative Humidity Sensor Capabilities and Limitations

The hygristor provide measurements from 0 to 100%. The accuracy of the sensors is about ± 5% and the response time is on the order of seconds. However, at temperature below -30°C the response time of this sensor can exceed 2 minutes and their accuracy is not fully established.

2.2.2.4 Radiosonde Transmitter and Battery

2.2.2.4.1 Radiosonde Transmitter

The radio transmitter electronics used on radiosondes transmits data pulses that represent one of the radiosonde sensor measurements or an internal electrical reference. The data are transmitted in a repetitive cycle of pressure, temperature, RH, and reference measurements. This produces a sampling rate of about 1.7 seconds for each of the radiosonde sensors. The transmitter power is 250-350 milliwatt with an amplitude frequency that can be manually tuned from about 1668 to 1700 MHz. This power is sufficient for the IMS-1500C to receive the signal at distances exceeding 250 km.

NOTE: The basic IMS-1500C Receiver Assembly characteristic for tuning frequency is 1668.4 – 1700MHz. You should not tune the frequency below 1675 prior to release.

The transmitter is housed inside the radiosonde casing to protect it from the elements.

2.2.2.4.2 Battery

A water-activated battery is used for generating power to operate the radiosonde. The battery is not factory installed and is wrapped in foil or plastic. To activate the battery, remove from the battery package and soak it in water for the prescribed time (2 minutes). After activation the battery is placed inside the radiosonde casing and will provide adequate power for up to 135 minutes. It is very important to follow the battery preparation instructions provided in section 2.8.5. It is essential for the batteries to reach proper voltage prior to baseline.



2.3 Radiosonde Balloon The success of the radiosonde observation depends upon the performance of the lighter than air gas filled balloon. The balloon lifts the radiosonde at a predetermined rate of ascent through the troposphere and stratosphere, for periods typically lasting from 90 to 120 minutes.

2.3.1 Balloon Inflation and Performance The burst altitude of a balloon is affected by:

• The free lift (number of grams of lift available over and above that required by a balloon to just support the weight of a complete flight-train and radiosonde),

• The air mass through which the balloon ascends and the weather conditions to which it is exposed, and

• The thickness of the balloon skin and the size and shape of the balloon envelope. Ascent rate is affected by free lift and drag. The amount of free lift required for producing optimum performance shall be determined before the balloon is inflated. Optimum performance is usually defined as the highest possible bursting altitude with an average ascension rate favorable for obtaining winds aloft data and for properly ventilating the radiosonde sensors (RH and temperature). The balloon must be sufficiently inflated to ensure successful release in the surface conditions which may exist at the time. These factors include, but are not limited to, the following considerations:

• During fair weather conditions, optimum performance and free lift will normally be achieved with 800-1300 grams of hydrogen or helium for 600-1200 gram balloons; 800-1000 grams of hydrogen or helium for 300 gram balloons; and 600-800 grams of hydrogen or helium for 100 gram balloons. The standard, average ascension rate should be 300 meters per minute. However, consideration should be given to how individual balloons produced by different manufacturers will perform based on their shape and thickness characteristics. Refer to manufacturer's instructions for recommended gas inflation amounts for specified ascension rates.

• The performance obtained by preceding flights should be considered in selecting a free lift value to be used.

• When precipitation, icing, or terrain turbulence is occurring, sufficient free lift shall be provided to ensure that the balloon will not descend or float. An increase of 100 grams free lift is typically sufficient to compensate for an increase in the weight of the train resulting from light precipitation. Under light or moderate icing conditions, moderate to heavy precipitation, or terrain turbulence induced by high surface winds, an increase in free lift of 200 to 300 grams will usually be sufficient. Under severe icing conditions, an increase of 500 grams or more may be required.

2.4 Radiosonde (NWS) Balloon Types Radiosonde balloons are spherically shaped films of natural latex or synthetic rubber (e.g., neoprene) which, when inflated with helium or hydrogen gas are used to transport the radiosonde flight train into the upper atmosphere. The skin of these balloons is extremely thin, except at the neck. When inflated, the wall of the balloon ranges in thickness from 0.051 to 0.102 mm at sea level to 0.0025 mm at typical bursting altitudes of 30 km or higher. Additionally, the balloon expands in size from an approximate release diameter of 1.85 m to an expanded diameter of 7.4 to 9.8 m at burst altitude. Considering these dimensions, it is obvious that the smallest cut, bruise, abrasion, scratch, or undue strain the balloon may sustain during



pre-flight preparations is likely to cause the balloon to burst prematurely at a lower altitude than it would normally attain.

2.4.1 Routine Upper-Air Soundings The NWS normally uses general purpose balloons rated to achieve burst heights of either 26 kilometer or 30 kilometers. These balloons are used under normal weather conditions when winds are relatively light and there is little threat of moderate or greater icing conditions. These balloons are thin skinned and are light weight to reduce the required volume of inflation gas needed to maintain proper ascension rates. Ascent rates should average between 275 - 350 meters per minute throughout the flight. Observations with ascent rates of 250 meters per minute or less may be the result of under-inflation or possibly a leaking balloon. Observations with ascent rates of 500 meters per minute or higher should be checked closely for a possible leaking or failed pressure sensor. If a leaking or a failed pressure sensor is discovered all data from that point in the flight on should be deleted and the flight terminated.

2.5 Flight Performance Balloon performance is measured by the burst altitude and ascent rate. Performance is affected by the free lift, the thickness of the balloon skin, the air mass overlying the observing site, the atmospheric conditions to which it is exposed, and the size and shape of the balloon envelope. Since most of these factors are uncontrollable, the free lift to produce optimal performance for any given sounding can best be determined by experience. INFLATION LIFT REQUIREMENTS: The amount of hydrogen, helium, or natural gas most favorable for producing optimum performance should be ascertained before actual inflation of the balloon. Lift is defined as follows:

1. FREE LIFT: Free lift is the number of grams of lift that are available over and above that required by a balloon to support the weight of a complete radiosonde train.

2. NOZZLE LIFT: Nozzle lift is the FREE LIFT plus the grams of lift required by a balloon to support the weight of a complete radiosonde train. Excluding the weight of the balloon (radiosonde, parachute, light stick, unwinder or train regulator, and twine).

3. GROSS LIFT: Gross lift is NOZZLE LIFT plus the grams of lift required to support the weight of the balloon.

The amount of gas required for producing optimum performance is usually defined as the highest possible bursting altitude while maintaining an average ascension rate greater than 275 meters/minute. The balloon must be sufficiently inflated to ensure successful launch in the surface conditions which may exist at the time. These factors include, but are not limited to, the following considerations:

• During fair weather conditions, optimum performance will normally be achieved with free lift ranging from 700 to 1000 grams for 26 kilometer general purpose balloons.

• During periods of high surface winds, the chance the balloon will hit an obstruction while being removed from the inflation shelter increases substantially. The balloon must be sufficiently inflated to clear all surrounding obstacles. The use of high-modulus balloon should be considered with wind speeds of greater than 25 knots.

• The performance obtained by preceding flights may be considered in selecting a free lift value to be used.



• When precipitation, icing, or terrain turbulence is occurring or expected, an effort should be made to provide sufficient free lift to ensure that the balloon will not descend or float. An increased free lift of 100 grams is typically sufficient to compensate for an increase in the weight of the train resulting from light precipitation. Under light or moderate icing conditions aloft, moderate to heavy precipitation, or terrain turbulence induced by high surface winds, an increase in free lift of from 200-300 grams will usually be sufficient.

• Attach the weights required to give the desired nozzle lift to the inflation nozzle - making allowance for the part of the hose that will be supported by the balloon as well as the nozzle itself, hose clamp, cutoff valves, etc., usually 200-300 grams.

NOTE: It is important to remember that the lift capabilities of hydrogen and helium differ. Hydrogen the lighter of the two gases lifts 31.8 grams per cubic foot at sea level while helium lifts 28.2 grams per cubic foot at sea level.

2.6 Balloon Storage and Handling Balloons shall be stored in their original sealed containers in a room isolated from large electric motors or generators. The ozone emitted from motors and generators causes synthetic rubber to deteriorate. Ideal temperatures for storage should be in the range of 10°C to 30°C. Balloons deteriorate with age. Therefore, they should be used in the order of their production dates to avoid excessive aging. Balloons are very delicate. No part of the balloon other than the neck should be touched with bare hands. Use soft rubber gloves, soft cotton gloves, or the plastic bag in which the balloon was wrapped when handling any part other than the neck.

2.7 Inflation Gases Two types of gas are used to inflate weather balloons: hydrogen and helium gas. HYDROGEN: Although hydrogen gas is more volatile than helium (which is non-flammable), most land based locations use hydrogen because of less cost. The price of hydrogen is only a fraction the cost of helium. Safe practices must be strictly adhered to when handling and using hydrogen. Hydrogen is either manufactured and bottled by a gas distributor or produced on site with a hydrogen generator. HELIUM: Helium is safe and easy to use for inflating balloons. Unlike hydrogen, helium is an inert gas and does not pose any fire potential. However, helium must be mined as a by-product and is limited in quantity.

2.8 Pre-Flight Preparations Pre-flight preparations are an integral part of ensuring a successful upper-air operation. The procedures taken during pre-flight will decrease the chance of having failed flights because of defective parts, or from using improper procedures. The observer must follow safety procedures that pertain to the site as indicated in Chapter 9 and should be observant of changing weather conditions that may affect the decision on the flight train components, amount of gas, and the type of release that should be attempted. Observers should routinely look at the upper level wind charts and the wind profile from local radars if available. The information provided from sources should help the observer decide which type of balloon and train components to use and what direction the balloon should travel upon release. Knowing this



information along with following proper pre-release procedures should help increase the chances of a successful signal lock-on and flight.

2.8.1 Flight Train Components The train consists of the balloon, parachute, cord, regulator, and radiosonde plus lighting and shock units as appropriate. Assembly procedures shall be designed to minimize strain on the balloon neck, avoid entanglement of train components, reduce risk of collision with ground obstacles, and prevent unrepresentative atmospheric sensing.

Figure 2-7: Flight Train

2.8.1.1 Balloon

The upper-air balloon must be properly inflated, tied, and secured before any other flight train components are fastened onto the flight train cord. Before the balloon is removed from the inflation nozzle, shut-off the gas from the cylinder. Tie the neck of the balloon with a double cord as soon as inflation is completed (see section 6.4.3.4). Remove the balloon from the nozzle. Next, carefully fold the balloon neck upward and tie with a square knot. Secure the balloon inside the inflation shelter by tying it to a hook or the measuring weights.

2.8.1.2 Train Cord

Train cord shall at least be a 20-ply string with a minimum of 25 meters length. A doubled 2 meter length of cord is needed between the neck of the balloon and the parachute. The remaining train length will be normally a single 20-ply string tied from the bottom of the parachute to the radiosonde. Use a train length of 25 to 35 meters under normal conditions. Trains of less than 25 meters in



length should never be used. Short trains increase the risk of the radiosonde being too close to the radiation environment of the balloon or of encountering the balloon’s wake as it ascends thereby placing the radiosonde in a disturbed and unnatural atmosphere. Erroneous temperatures and relative humidity may result.

2.8.1.3 Parachute

Parachutes shall be used at all stations unless the local Government Weather Service Headquarters issues a station waiver. The color of the parachute is bright orange that can be distinguished from the sky background during daytime operations. The parachutes are designed so that the flight trains fall at a rate 10 m/s (22 mph) or slower by the time it reaches the ground.

2.8.1.4 Train Regulator and Unwinder

For other than normal release conditions, particularly for high winds release conditions, observers may be required to use a train regulator or unwinder. Use a maximum of 2 meters of doubled cord between the neck of the balloon and the parachute, tie the train regulator or unwinder to the bottom of the parachute and the ring or loop at the top of the radiosonde to the free end of the train regulator or unwinder. Train regulators and unwinders enable the observer to launch an instrument without having to contend with many yards of slack twine or having to chase the balloon to release the radiosonde. When a train regulator is used, the balloon is held in one hand and the train regulator and radiosonde are held in the other. The train regulator is held in such a way that neither the weight of the radiosonde nor the lift of the balloon unwinds any of the cord until release. At launch, the balloon is released and almost simultaneously, the radiosonde is released. As the balloon rises, the weight of the radiosonde causes the cord to unwind from the train regulator or unwinder. The radiosonde train regulator consists of a frame, reel, and braking mechanism. The regulator is furnished with approximately 30 meters of twine or nylon tape wound on the reel. The braking mechanism permits the weight of the radiosonde to unwind the twine at the nominal rate of 1 meter per second. The regulator is designed to withstand the stresses placed on it in normal use. Care must be exercised to avoid unnecessary strains which might ruin the gear train and braking mechanism. Before using a regulator, test it by firmly pulling about 2 meters of cord from the reel. Should the reel feed out too rapidly, it may be adjusted by squeezing the metal braking pawls together with pliers. If the braking pawls are too tight, the regulator will not feed out. To use, place the free end of the twine through the eye or over the spacer at the bottom of the regulator. Tie the twine to the supporting ring or loop at the top of the radiosonde. Determine that the regulator operates normally when supporting the weight of the radiosonde. Then rewind the twine by rotating the reel manually. The Radiosonde Train Regulator shall be rigged as shown in figure 2-8.



Figure 2-8: Regulator Rigging Diagram

The unwinder (see Figure 2-9) is a plastic apparatus that toggles back and forth as the line is pulled off the unwinder due to weight of the radiosonde. It is a very simple device that requires care in making sure the unwinder is securely tied to the cord from balloon or parachute at selected notch. The cord will unwind faster from the middle position and slower tied to the end position.

Fast release↓ ↓Slower release

Figure 2-9: Unwinder

2.8.1.5 Shock Unit

During high winds, a shock unit may be used in the radiosonde train between the regulator and



the radiosonde if vibration caused by the inconsistent unwinding of the regulator is expected to produce an unstable signal. The shock unit may be formed by tying together in parallel four 0.125 inch wide rubber bands. The rubber bands are tied to the cord of the train in such a way that the cord is slack between the ends of the bands, thereby permitting them to flex and extend when the line goes under tension. In this way the shock unit acts as a shock absorber.

2.8.1.6 Light Stick

Most tracking systems require the observer to visually track the radiosonde and manually adjust the antenna position to ensure the receiving system is locked onto the radiosonde signal. This can be a problem at night or in poor visibility if the radiosonde trajectory is expected to experience large changes in direction e.g., from low level wind shear, restricted visibility or low cloud heights, or high elevation angles due to calm or light winds at release. When visibility is restricted or at night, the observer shall ensure a lighting unit is attached to the flight train to facilitate visual tracking of the balloon for the early part of the observation. The lighting unit will also help the observer relocate a flight train higher in the ascent if the receiving system has lost the main signal. The lighting unit intensity should be such that the radiosonde position can be distinguished from the background for at least five minutes. The National Logistics Supply Center (NLSC) stocks various colored light sticks that are attached to the flight train. Care must be taken to ensure that lighting units will not interfere with the braking mechanism of a train regulator. This can be successfully accomplished by tying the light unit near the balloon’s neck with little slack to keep the light stick from swinging in the wind.

2.8.1.7 Radiosonde

The Radiosonde is tied to the flight train so that it holds the lowest position in the radiosonde flight train.

2.8.2 Flight Train Requirements

2.8.2.1 High Surface Wind

Under high wind, (e.g., 25 kt) a train regulator or unwinder may be required. The observer should tie the end of a 2 meter length of double cord to the neck of the balloon and the parachute. The train regulator or unwinder should then be tied to the bottom of the parachute with radiosonde attached to the line from the train regulator or unwinder. The balloon should be inflated to attain a nozzle lift that is 10% to 20% greater than fair weather launches. Launches in very high wind conditions (e.g., 40 kt) pose special problems in protecting the flight equipment until it becomes airborne. The balloon should be inflated to attain a nozzle lift that is 20% to 30% greater than fair weather launches. Assistance from another observer may be required to avoid obstructions and to ensure a successful launch.

2.8.2.2 Heavy Precipitation

The observer may attach a light stick to improve visually locating the radiosonde to allow manual adjustment of the tracking antenna. The balloon should be inflated to attain a nozzle lift that is 10% to 30% greater than fair weather launches.

2.8.3 Balloon Inflation The balloon inflation should begin no more than 45 minutes prior to release. Safety procedures must be followed.



2.8.3.1 Safety Procedures

Place the balloon where it will not come into contact with sharp objects or rough surfaces. If the dimensions of the inflation shelter permit, the balloon should be placed on a table for inflation. The table top should be smooth, free from projections and have all edges rounded. The table top should be cleaned frequently. To reduce abrasion during inflation, the table should be large enough so the balloon can be fully extended before the inflation is started. If it is not practical to use a table, the balloon should be placed on a clean surface with all objects with sharp points removed from the immediate vicinity of the balloon. Place the inflation nozzle in the neck of the balloon and secure it with a clamp, soft cord, or other suitable device which won’t damage the balloon.

2.8.3.2 Proper Inflation Rates

HYDROGEN: When hydrogen is used, open the valve to a pressure not exceeding 15 psi. Inflation should take no less than 7 minutes. If the balloon is rapidly inflated with hydrogen gas the likelihood of generation of static electricity is greatly increased and with it, the hazard of a fire or an explosion.

2.8.3.3 Inflation Procedures

2.8.3.3.1 First Stage in Inflation

When the balloon has been prepared and inflation equipment (cylinders, hoses, clamps, safety switches) is confirmed to be in good order, begin the inflation of the balloon in accordance with guidelines.

2.8.3.3.2 Intermediate Inspection

When the balloon is about one-half inflated, close the gas valve. Listen for gas leaks and examine the balloon for defects. Serious defects may result from foreign materials in the neoprene, a break in the balloon skin, or a deformity in a small area of the neoprene film. Discoloration should not be regarded as a defect unless experience indicates that certain types of discolorations result in premature bursting. If the balloon is defective, reject it and begin inflating a second balloon. Otherwise, proceed with inflation.

2.8.3.3.3 Final Inflation

Once the balloon is at least partially inflated check to ensure the balloon is not in contact with the ceiling of the inflation shelter or any other surface. If the balloon is likely to touch the ceiling before the desired lift has been reached, proceed carefully with the inflation and secure the balloon in manner to minimize or eliminate any possible contact with the ceiling or other objects. Sites having low ceilings should use padding or netting to ensure the ceiling is smooth and protected by soft material.

2.8.3.3.4 Securing the Balloon

Tie the neck of the balloon with a doubled cord as soon as inflation is completed. Make one turn of the cord around the neck of the balloon near the center (close to the top of the inflation nozzle). Pull the cord as tightly as possible and tie with a knot. Make another turn around the neck and tie again. Remove the balloon from the nozzle, fold the neck upward and again tie the neck just above the first knot. Be sure that all cord is below the area where the neck starts to flare out to join the envelope of the balloon. The balloon should be left in the inflation shelter until preparations for the release have been completed.



2.8.3.4 Launch Delays

Balloon inflation should not occur earlier than 45 minutes prior to release. Allowing the balloon to be inflated an extended period of time before the launch causes undue strain on the balloon and is likely to cause premature bursting. At sites using helium, the balloon may be allowed to rest against the ceiling of the inflation room provided the ceiling is smooth and free from projections or rough spots. Balloons inflated with hydrogen or natural gas should not rest against any surface other than an anti-static balloon cover or shroud once removed from the inflation nozzle.

2.8.4 Fastening the Flight Train Together Whenever possible, the station workload should be arranged so that release can be made within a few minutes following the testing and calibration of the radiosonde. The flight train should be completely assembled and ready for launch within 20 minutes from the time the battery cell was activated. The train is normally assembled during the balloon inflation process which is normally performed 30 to 45 minutes prior to release. Flight train assembly at the time of launch should normally be avoided and should only be done if the observer is sure that launch will occur within 20 minutes of battery activation time. Proper assembly of train (i.e., the balloon, parachute, radiosonde, and any launching devices which may be used) is critical to the success of the observation and the accuracy of the data. Improper train assembly could result in:

a) Undue strain on the balloon neck and premature termination of the flight.

b) Unrepresentative sensing of the atmosphere.

c) Entanglement of components.

d) Higher risk of collision with ground based obstacles.

e) An increased hazard when the radiosonde flight train descends if the parachute doesn’t deploy.

I. THE INITIAL TYING OF LINES ONTO PARACHUTE AND BALLOON A) Tie a 2 meter length of double strand 20-ply cord to the top of the parachute. Leave

free the other end of this cord. (If a parachute is not required, see item III for instructions.)

B) Follow procedures outlined in section 2.8.3.3.4 on securing the balloon.

II. LINKING THE TRAIN REGULATOR OR UNWINDER TO THE FLIGHT TRAIN When a train regulator is to be used follow these procedures

A) Tie the train regulator or unwinder to the lower end of the parachute. Care must be exercised when using an unwinder to ensure that the unwinder is secured properly. This may be done by making several wraps around the unwinder when securing it to the lower end of the parachute or by adding another .3 to .6 meters of doubled string between the bottom of the parachute and the unwinder.

B) If a parachute is not used, ensure the doubled-cord is secured firmly around the train regulator’s spindle (axle). If an unwinder is used, it should be secured to the balloon by placing the unwinder handle in the fold of the neck of the balloon and secured firmly with several knots to ensure the handle can not slip out.



III. TYING FLIGHT TRAIN WITHOUT A PARACHUTE TO THE BALLOON The final phase of the flight train assembly is to link the train assembly to the balloon. The assembly is dependent of the flight train’s configuration.

A) For flights that require neither a parachute nor a train regulator/unwinder: Follow the instructions in item I. B. Fasten the free end of the 2 meter doubled cord to a 23 - 35 meter length of single 20-ply cord with the free end attached to the radiosonde.

B) For flights that require a unwinder but no parachute: Again follow the instruction in section 2.8.3.3.4 but place the handle of the unwinder at the point on the neck of the balloon where the original knot was tied and then fold the neck up and secure the unwinder by wrapping several turns of the doubled cord around the unwinder hook or arm and tying a tight knot. Release the suspension string from the slot of the unwinder and tie to the metal eyelet on the top of the instrument.

C) For flights that require a train regulator but no parachute: Fasten a 2 meter length of doubled-cord to the balloon’s neck following procedures shown in section 6.4.3.4 titled securing the balloon. Then secure the end of the remaining amount of doubled-cord to the train regulator. The line from the train regulator should then be tested by firmly pulling a small length of line from the regulator and attaching it to the radiosonde eyelet.

2.8.5 Radiosonde B2 Pre-Flight Preparation

2.8.5.1 General

1. The VIZ B2 Radiosonde is entirely built within a strong, but lightweight expanded polystyrene foam case, consisting of the main body, the cover, and a waterproof white fiberboard sleeve which is imprinted with mailing bag instructions.

2. When shipped, the radiosonde is placed in its mailing bag before being packed in the carton. After baseline testing, the mailing bag is to be placed, tightly folded, in the well which the hygristor occupied. Then the sleeve is replaced over the case.

3. If possible, radiosonde checkout should be accomplished upon receipt of a radiosonde shipment; otherwise it will be done at the time the radiosondes are being checked for baseline flight check.

4. Open the carton of 16 radiosondes and remove the radiosondes for inspection.

5. Take the radiosondes out of the bag and hold upright, with the word “FRONT” facing you (Figure 2-10). The humidity sensor storage space, battery storage space and humidity duct access cover are on your left. The main body lid is on your right. This lid is sealed to the case with RTV. The temperature sensor in its mounting is directly behind the front face of the fiberboard sleeve with the sensor in a protective depression.

2.8.5.2 Checkout Assembly

1. With the radiosonde upright with the front panel facing you, bring the lift cord over the top, to the back side of the sleeve. Push the foam case up from the bottom until it is about one inch above the outer sleeve. Lay the sonde on the table with the mailing instructions on the top surface. Grasp the foam case with one hand and the bottom of the sleeve with the other and gently slide them apart. A white corrugated sheet with three access doors should be on top (see Figure 2-11).

− The small door to your right exposes the hygristor mount.



− The center door provides access to the battery which is housed in the foil bag.

− The door on the left covers a well containing the humidity sensor can.

− The white temperature outrigger is lying down in its protective well.

Figure 2-10: VIZ B2 Radiosonde

2. Remove the humidity sensor can from its well and set aside. Do not open the can yet.

3. Turn over the radiosonde so that the white corrugated sheet is on the bottom and the orange and black power cable is facing you. This lid is sealed to the case with RTV. The meteorological data oscillator (MDO) assembly printed circuit board is mounted edgewise in the center. The radio frequency transmitter is in the end of the board with the RF tuning capacitor. Access to the tuning capacitor is under the RF tuning plug (white vinyl plug) where the power cord comes out on the sonde.

4. Visually inspect the following assemblies for defects:

− Thermistor: sensor broken, coating scratched

− Humidity clips: broken or bent



if either the thermistor or humidity clips are defective, return the complete radiosonde (battery, hygristor, sleeve etc.) for warranty repair.

5. Power source; radiosonde testing shall be done with a power supply source other than the radiosonde battery when one is available. If a power source is not available, a radiosonde battery will be used to test as many radiosondes as possible before the battery voltage drops below 17.5 volts.

6. If not already done, turn on the ground system and let it warm up for at least 15 minutes as if setting up for an actual flight.

7. Check the calibration disc to ensure that it can be read and that the calibration data is for the radiosondes in the carton. Calibration Data disk should be loaded on the computer upon receipt and the floppies should then be safeguarded until all the radiosondes from the box have been used. If it can not be read or is missing, contact the NWS Upper Air Program Office for disposition instructions.

8. Check the radio and audio frequency tests to be certain that the radiosonde is functioning. The received capacitance pressure references shall be checked to see if they are in an acceptable range. If the ground system indicates a failure in one of the parameters, reject the radiosonde and return for warranty repair.

9. The pressure indicated by the radiosonde at baseline, and before the surface pressure correction is applied, shall not deviate from the actual station pressure by more than 5 hPa. If the pressure difference is greater than 5 hPa, reject the radiosonde and return for warranty repair. If the radiosonde checks out OK on the preliminary checks put the components back into the radiosonde and place the radiosonde back in the mailing bag before placing in the shipping carton for operational use at a later date.

2.8.5.3 Preflight Baseline

1. Turn on the ground system and run for at least 15 minutes. Plug the radiosonde to the power source or battery for 5 minutes to allow it to warm up. If a power supply is not available, the radiosonde battery will be used to test the radiosonde after the battery voltage reaches 17.5 volts. The ground system will confirm if the radiosonde is reading correctly.

NOTE: Not allowing this warm-up time may cause needless baseline failures.

2. Calibration data for the radiosonde are supplied by way of floppy disc.



Figure 2-11: Radiosonde with Sleeve Removed



Figure 2-12: Radiosonde Foam Box

Note: Figure 2-12 the baseline foam is an oblong object, made from polystyrene, with dimensions approximately 17cm x 32.5cm x 10cm. A B2-sonde foam box may be used in lieu of the solid box, minus the following: MDO Board, Hygristor/Thermistor Assembly. Humidity can. Place radiosonde on lid side of box.

2.8.5.4 Installing the Hygristor

1. Position the radiosonde so that the white corrugated sheet is on top, the white temperature outrigger arm is facing you, and the hygristor mount is in its nest beneath the door.

2. The hygristor element is packed in a closed, airtight container for shipment. The container should not be opened before flight. Keep the opened lid of the can until ready to install the hygristor in the duct.

3. Once the container is opened, the operator should carefully handle the hygristor by its edges only. This will ensure that the operator’s skin or other foreign objects do not contact the hygristor film.

4. If contact with the film should occur, the hygristor must be rejected. With the precautions noted above, open the container and remove the hygristor, holding the edges between the thumb and the forefinger of your hand. Lift the hygristor mount door.



5. While holding the hygristor in your hand, insert it downward through the door using the forefinger of your other hand to assist. Insert the hygristor between the upper two clips (see 2-14). Move it downward until the end touches the lower clips. Tilt the top of the hygristor away from you very slightly so that the lower far corner can fit inside the lower clips. Again using the forefinger of your hand to assist, push the element end into the lower clips.

6. Once properly mounted, slide the element up and down a bit to ensure good contact. Next, center the element, vertically, in the duct. If necessary, adjust the tension on the clips. Be certain the hygristor mount door is closed.

NOTE: While holding the hygristor, take caution not to touch the coating. If the coating is

touched, the hygristor must be rejected.

Figure 2-13: Hygristor and Clips

2.8.5.5 Battery and Preparation for Sounding

1. Battery preparation will be done in accordance with the following battery preparation instructions.

a. With the battery positioned such that the label faces upward (Top-Up position) immerse it is fresh drinking water to a minimum depth of 1” below the surface of the water. Do not allow the socket to become wet. Leave in the water for 2 minutes.



b. Remove the battery from the water and while holding the battery with the label facing downward (Top-Down position) remove excess water by extending arm and swinging the battery in an arc beginning over the head and stopping abruptly at the knees. Repeat this motion at least four and no more than ten times. It is important that the surface containing the battery label be facing downward (Top-Down Position) during the shaking operation.

c. Examine the partially waxed sides of the battery for any remaining excess water in the unwaxed areas. Repeat the shaking operation if excess water is found. The excess water greatly increases intercell leakage, causing overheating of the battery and shorter life.

d. Enclose in either plastic tube or bag and place on normal dummy load until the proper 17.5 volts is reached.

2. Vent the open end of the tube or bag outside the radiosonde case. Remove the connection to the dummy load. Place the battery in the plastic bag so that the “TOP” is up and the cable exists from the open end. Install the battery with “TOP” facing the hygristor mount. Thread the cable and bag beneath the white corrugated sheet for venting. Join the Radiosonde MDO power connector and the battery connector. Return the cable beneath the sheet.

3. All stations using parachutes will place a return mailing bag inside the hygristor well. Enter the Radiosonde serial number, name of station, date and schedule time of observation (UTC) on the front of each tab. Make all entries with permanent ink.

4. Place bag flat on the table with the glue flap facing up and the open end away from you. Fold in thirds, towards open end, wiping the air out while folding. Fold in thirds again. Fold in thirds again in the length. Fold in half and place in the well previously occupied by the hygristor can.

5. If the radiosonde need to be re-tuned, place it on the baseline foam (or suspend it on a string from the ceiling) so that the RF frequency will be the same as in flight. (See Figure 2-14)

6. Remove the vinyl plug and tune through the hole with a tuning stick. Clockwise will lower the RF frequency, counterclockwise will raise the RF frequency. Replace the vinyl plug with the open end facing out.

NOTE: When performing the radio and audio frequency tests, be certain to stand at least 3

feet away from the radiosonde. When baselining the radiosonde, (tuning RF, checking audio frequencies, etc…), place the Radiosonde on the Baseline Foam, see Figure 2-12. Do not retune the radiosonde frequency unless it is more than 5 MHz different from 1680 MHz.

7. Bend the temperature outrigger arm up 135 degrees.

8. Stand the radiosonde vertically so that the temperature sensor is to your right. Stand the outer sleeve such that the “FRONT” is to your right.

9. Pick up the foam case. Put it into the top sleeve opening, with the mailing instructions facing you. Slowly lower it. When the foam case is entirely in the sleeve bring the lift cord back over the top, and pull the open end of the battery bag out of the slot to the left of the mailing instructions. Figure 2-15 shows the radiosonde with the battery properly installed.



10. Ensure that the bottom string is over the bottom of the radiosonde and that the knot is tight. Place the radiosonde onto the baseline foam.

11. The radiosonde is ready for flight. Follow the usual flight routine as per instruction in this handbook.

Figure 2-14: Radiosonde Temperature Arm



Figure 2-15: Radiosonde with Battery Installed

2.9 Transportation of Instrument to Release Point Once a successful baseline is obtained, the antenna should be positioned to point in the approximate direction the balloon is expected to travel with the elevation adjusted for wind conditions. FLIGHT READY message in status bar will be replaced by FLIGHT READY FOR LAUNCH

2.10 Final Inspection of Flight Train After the balloon has been filled and the flight train has been assembled, inspect the tie points along the flight train to ensure cord connections are fastened tight. Ensure that the balloon



neck is not being overly strained. Ensure the train cord to the radiosonde is untangled and will flow freely through the hand or through the train regulator. Do not forget to check the cord at bottom of radiosonde to ensure it has been tightened properly. Release procedures vary with the wind conditions at the release site. The observer should be familiar with all obstructions about the area before attempting a release. Before the balloon is removed from the inflation shelter, the observer must recheck the wind direction and speed. Visually check to confirm that the temperature and humidity sensors are properly positioned and not damaged. Ensure the battery is firmly encased within the body of the radiosonde. Observers are reminded that high winds and heavy precipitation increase the risk of flight train entanglement in trees, high-tension power lines, and various antenna masts. To the extent possible, measures should be taken to reduce the possibility of entanglement (i.e., add extra free lift during inflation). If entanglement with a power line or antenna mast occurs, no attempt shall be made to disentangle the rawinsonde. The circumstances should be reported at once to the relevant power company, broadcast station, or Communication Company.

2.11 Final Safety Check No matter where an upper-air site may be located care must be exercised prior to launching a rawinsonde flight.

2.11.1 Notify the Local Tower Follow your station procedures for an upper-air site located within 5 nautical miles of a controlled airfield. NOTE: A visual check of the horizon shall be made at all upper-air sites prior to Launching of

the radiosonde flight train.

2.11.2 Radiosonde Launch

NOTE: If radiosonde launch has been delayed and there is reason to suspect that surface data have changed following preflight data entry, re-enter the preflight data entry screen by pressing F5 or selecting Pre-Flight menu. Update relevant surface data and click OK. Screen will prompt as to whether entry of pressure offset correction is desired. Click YES or NO as appropriate. Flight screen will then reappear.

NOTE: The radiosonde must not be placed on the ground at any time! This can cause

antenna loading which will cause a frequency shift once the instrument becomes airborne. The frequency drop may be from 5 to 10 MHz. This drop in frequency may cause the receiver to go into a frequency search.

2.12 Flight – Starting the Flight iMetOS will start the flight after a 4mb decrease in pressure has been detected. NOTE: Never release into a thunderstorm, wait until it passes or do not make a release



2.12.1 Using the CDU

1. Steer the Antenna visually onto the radiosonde held by the operator at least 30 meters away if possible.

2. Ensure that the receiver is switched to “Manual” (AFC Off).

3. Select Receiver Search speed 2 and wait for “AFC ON” to be displayed. Ensure that Squelch is OO and that signal strength of at least 30 is indicated. If not, select “AFC OFF” and repeat Receiver Search.

4. Select TRACKING AUTO (ON) and ensure that the Antenna is pointed at the radiosonde, then return to OFF.

5. Wait for Status Line to indicate that PTU data is available.

6. Release Balloon and select TRACKING AUTO (ON).

2.12.1.1 Flight - Tracking the Radiosonde

During the flight the system will automatically track the radiosonde and record the flight data received from the radiosonde. Check that the tracking operates correctly during the early stages of the flight, in case temporary signal loss from the radiosonde causes the IMS-1500 to loose track of the radiosonde. The CDU can be used to check proper tracking by the antenna and steer the antenna back onto the radiosonde if tracking is lost.

2.12.1.2 Flight – Tracking the Radiosonde using the CDU

The CDU is used for local, direct control and monitoring of the operation of the Antenna. A subset of the command set implemented in the System Computer is implemented in the CDU. If the Antenna seems to following the radiosonde, but the radiosonde signal strength is to low, the Antenna may be locked onto a side lobe (displaced by 12 degrees from balloon). In order to correct, switch Tracking to MANUAL, steer the Antenna until the radiosonde strength has increased, and switch Tracking back to AUTO.

2.12.1.3 Flight – End of Flight

At the end of the flight, when the balloon bursts or when the required height has been exceeded, data reception may be ended from the CDU by selecting AFC to OFF and Tracking to MANUAL. Data logging has to be terminated at the System Computer.

2.12.2 Using the System Computer When radiosonde is ready for launch perform the following:

1. FLIGHT READY message in status bar will be replaced by FLIGHT READY FOR LAUNCH.

2. Proceed to release radiosonde.



3. The flight clock will start as soon as the system recognizes a pressure change of 4 mb. At this point, the message at center of screen will be replaced by FLIGHT IN PROGRESS.

On sonde release, altitude, ascent rate and PTU values displayed on screen will begin to change rapidly. Wind data and slant range will appear on screen about four minutes into the flight. The IMS-1500 system will operate independently throughout radiosonde flight. If the sonde signal is lost or indecipherable at any point during flight, NO DATA or BAD DATA warnings will appear on the screen and record display will stop. When the IMS-1500 relocates decipherable data, warning messages will disappear and record display will resume. Data received and processed during a flight may be displayed and/or printed in real time, as graphs or meteorological messages and reports.

2.12.3 Fair Weather Launches In the warm season, particularly when taking the 0000 UTC Observation, be alert to possible super-adiabatic lapse rates in the first 10 meters above the surface. Similarly, throughout the year, particularly at the 1200 UTC observation, be alert for layers in the first 30 meters above ground level that have been cooled by radiation inversions.

2.12.4 Calm Wind Launches On occasion, the IMS-1500 antenna will lockup when the rawinsonde becomes positioned nearly above the tracking unit. This may occur when winds are calm at the surface, or if winds bring the radiosonde over the station and into a layer of light and variable winds aloft. When the tracking antenna is stuck in a high elevation angle position, override the AUTO tracking system and manually control the antenna to a slightly lower angle. Then search and reacquire radiosonde’s signal through full and limited-scale frequency scanning and manual antenna repositioning with visual tracking, if necessary. In many cases, the software will detect a locked antenna and automatically delete the position data during the period of the lockup. However, if this period is short, the software may not detect the lockup.

2.12.5 Heavy Precipitation Heavy precipitation is defined as 0.30 inches per hour or more than 0.03 inch in 6 minutes. This rate will place loading on the balloon and result in slower ascent rates during the first portion of the flight. General guidelines for heavy precipitation events:

• Use extra gas (free lift)

• Possibly launch earlier or later if the precipitation is expected to move through the area or diminish in intensity.

2.12.6 High Winds The observer should be aware of the obstructions around the upper air shelter before attempting a release. Before the balloon is removed from the inflation building, the wind



direction and speed shall be determined. Note the period of gusts and type of turbulence that could pose a risk to the rawinsonde flight release.

2.12.6.1 Two Person Technique

If a train regulator or unwinder is unavailable or time does not permit the reconfiguration of a flight train and an assistant can lend a hand, the two person technique is recommended for high wind cases. This technique can be conducted from the standard inflation shelters. NOTE: The two observers should plan the radiosonde release in advance for the technique

to be successful

The first observer will hold the tie-ring or cord above the radiosonde in one hand, grasp the cord further up the train with the other hand and extend the train until a slight tension is exerted to avoid having the train become tangled. The second observer will then remove the balloon from the shelter; the balloon will be taken as rapidly as is practicable to the preselected site, with the first observer ensuring that the cord does not become tangled. The observer holding the radiosonde should be positioned downwind from the balloon so that it will pass directly overhead when the weight of the radiosonde is assumed. Correct positioning is the responsibility of the observer with the radiosonde since under these conditions the observer with the balloon will find it more difficult to change position. When the release area is reached, the observer holding the balloon will release the balloon and the instant the train slackens, the first observer will run downwind until the balloon takes up the slack. As this happens, the first observer will raise the radiosonde with one hand and bring the cord forward in the other hand. If the movement of the hands is coordinated, the radiosonde will follow the balloon with no noticeable jerk. When obstructions prevent the observer with the radiosonde from running downwind, the observer holding the radiosonde will stand in a position to observe the movement of the balloon. At the instant the balloon takes up the slack, the observer will follow through with the radiosonde to reduce the jolt and any possible damage to the radiosonde.

2.12.7 Thunderstorm The radiosonde shall not be launched into thunderstorms. Thunderstorms can degrade the radiosonde signal or force the balloon down causing early flight termination. In addition, a thunderstorm and its immediate surroundings are unrepresentative of the prevailing environment. Wait until the storm passes before doing a release. If the storm persists beyond the release window, no observation shall be taken.

2.12.8 Delayed Release The radiosonde should be released within the officially prescribed time limits. If a release is delayed beyond the time limit, careful consideration should be given to replacing the battery.

2.13 Maintaining Proper Signal Lock-On The tracking antenna receives radiosonde radio signals in two distinct patterns, one associated with the main lobe and the other the side lobes. If the radio-theodolite system locks onto a side lobe instead of the main lobe, the position data are incorrect and tend to be very erratic with time. Wind data determined to be derived from side lobe tracing are in error and shall be deleted.



At times owing to signal interference (i.e., noise), weak or fading signals, or faulty ground equipment, erratic angular data may result. This situation for the RDF tracking equipment is most prevalent when elevation angles are below 12 degrees, but can occur at other angles as well. This situation can cause a spike to appear in the data. Sudden, abrupt changes in the 6-second elevation or azimuth angles of the antenna are not realistic and are caused by signals too weak to supply the ground receiver with an adequate reference or by the lack of tracking sensitivity in the ground equipment. Another type of erratic elevation angles with RDF tracking occurs when angles are greater than 12 degrees and at least 15 minutes of the observation have elapsed. In this case, erratic angles may be caused by equipment not operating properly, tracking a secondary lobe, or due to a signal loss. The result will be tracking errors in excess of predetermined tolerances in azimuth or elevation angles. Poor Tracking may cause erratic angles or spikes in the data caused by noisy or weak signals or ground equipment problems shall be smoothed or removed. MULTI-PATH PROPAGATION AND LIMITING ANGLES: Multi-path propagation causes the antenna to stay in one position for a short time and recover when it gets an adequate signal. This will cause the antenna to bounce creating plots of the elevation angles with steps, or waves, on the plots. This situation is most prevalent when elevation angles below 12 degrees are encountered and becomes increasingly pronounced as the elevation angles near 6 degrees. If multi-path propagation is determined to be occurring, the anomalous data shall be deleted. The limiting angle is the elevation and azimuth angle of the RDF antenna at which the antenna cannot successfully track the radiosonde owing to multi-path propagation. Limiting angles are no less than 6 degrees off the horizon or obstructions (e.g., mountains or buildings) along the horizon.

2.14 Multiple Releases Each upper air station shall track the radiosonde to the highest altitude possible. Care must be taken to ensure the observer checks and verifies the data is realistic and reasonable. Software checks and call-ups should be investigated and unrealistic data edited or eliminated prior to message transmission. If a radiosonde terminates before reaching 400 hPa, a second release may be required. When necessary, the second radiosonde should be released as promptly as possible in order to stay within the time limits of the scheduled observation. However, if because Of unfavorable atmospheric or other reasons, it is apparent that a pressure equal to or less than 400 hPa cannot be attained in subsequent attempts; an additional release should not be made. If a second release is not made and the record from the first one is usable, even though it did not extend to a pressure equal to or less than 400 hPa, the record from the first release should be evaluated and used for summary and transmission purposes.

2.15 Observation’s Success In order for an observation to be successful, all criteria for a successful release must first be met to satisfy the iMetOS software. The observation is finally deemed successful when the upper air sounding contains at least the required amount of data per three strata and must not have had more than 6 minutes of missing data from surface through 400 hPa. If the observation was not terminated for the reasons specified in Table 2-3 and has not failed, the observation is deemed



successful. An observation is deemed successful when reliable data from the surface to at least the 400 hPa level has been recorded. Sites using Sippican (VIZ) instruments receive meteorological data with quality values (Q-values). Site using the Sippican RDF radiosondes, the Q-value of 30 or more are valid. Data with Q-values less than 30 are invalid or unreliable and the software will mark them missing. The maximum permissible quantity of missing temperature data is provided in Table 2-3. An observation should be terminated when the, number of minutes, of missing temperature data as given in Table 2-3, are exceeded. The Table 2-3 represents the maximum tolerable amount of missing data, expressed in both strata thickness and time interval. NOTE: Observers should be aware that the iMetOS software will only terminate the flight for

data the software deems missing. Any additional data that the observer deletes will not be taken into consideration by the software program. The observer is responsible to ensure that the criteria in Table 2-3 are not exceeded.

Table 2-3: Termination Due to Missing Temperature Data

Pressure Range (hPa) Strata Thickness (km) Minutes of Missing Data Surface to 700 1 4 Surface to 400 2 6, with above criteria satisfied Surface to 100 3 12, with above criteria satisfied

Surface to termination 5 (upper <100 hPa)

16, with above criteria satisfied

2.16 Reasons for Missing Data

2.16.1 Weak Signal Weak or fading signals can result from a weak battery, a radiosonde moving too far away, or a ground tracking antenna that is not correctly locking onto the radiosonde signal.

2.16.2 Interference Signal interference has become a problem especially at sites located near large metropolitan areas. Any abrupt change in the audio or frequency is a good indicator of possible interference.

2.16.3 Sensor Failure Radiosonde sensors may fail. If the relative humidity sensor fails the flight can be continued if the relative humidity is not considered critical. If the temperature or pressure sensor fails, the flight should be terminated at the last reliable data point.

2.16.4 Successful Observation – Some Missing Data Whenever a stratum of missing temperature data is followed by a satisfactory record, the computations should be continued, provided the stratum or strata of missing data does not exceed the limits in Table 2-3, for “Surface to 700 hPa” and “Surface to 400 hPa”. When the limits are exceeded in one stratum of missing temperature data, the computations should be terminated at the base of the stratum.



2.16.5 Unsuccessful Observation – Sum of All Missing Data Whenever the limits for “Surface to 700 hPa” or “Surface to 400 hPa” in Table 2-3 are exceeded, the observation should be terminated at the base of the stratum in which the limits are exceeded.

2.17 Inflight Procedures After a successful balloon flight train release the observer shall follow procedures to ensure a successful flight.

2.17.1 IMS-1500C Control Display Unit (CDU) and Workstation Checks After return from the balloon release point, the observer should check the SMC readings and computer displays. If the signal strength is strong and the observer is confident the antenna is locked on the main signal, the position data should be checked to determine when lock-on occurred. The observer should keep the audio turned up loud enough to monitor the instruments tones and check for any interference or signal loss.

2.17.2 SMC CDU and Workstation Checks The observer must prior to release and after release verify the frequency and signal strength by using the CDU. The check prior to and after release with the CDU allows the operator the opportunity to reacquire the frequency or signal if lost. If the CDU is inoperative or the weather is inclement, the observer may have to wait until returning to the office to use the workstation to ensure the system is tracking effectively. The observer should utilize the status bar and Antenna Orientation Display on the workstation to verify equipment tracking and the signal strength after returning to the office.

2.17.3 Tracking Problems Any rapid loss of signal strength or quality, major fluctuation in angular readings, or shift in frequency should be looked at closely. Turning up the audio with the tracking system will allow the observer to monitor the signal quality and tones essential for the early portion of the flight where the chance of getting on a side lobe or another signal is most likely. If it is apparent that a significant change has occurred and the antenna is not tracking on the signal, the observer should take immediate action by checking the antenna position and signal strength. Depending on the observer’s analysis, either the antenna or the frequency will have to be adjusted.

2.17.3.1 Signal Problems

See section 3.7.1

2.17.3.2 Frequency Problems

If the frequency has made an abrupt shift or significant change since the release, determine if the signal being received is the radiosondes. If the signal is not from the instrument, the observer should immediately press the “Manual Search” button and toggle the frequency down in the direction where the signal was originally, stopping once the signal is acquired and pressing the “AFC” button to have the equipment automatically tracking the signal. If the signal should again track off the instrument’s frequency, it may become necessary to leave the tracking in a “Manual Search” until the other signal no longer interferes with signal acquisition. If an abrupt shift or change in the frequency of the instrument is noticed, the observer must determine that signal being received is from the radiosonde. The observer should then determine that the signal being tracked is from the main lobe and not from a side lobe. This can be determined by looking at the signal strength and listening to the signal’s audio output. If the



signal is weak or scratchy, the observer may want to go into “Manual Tracking” and adjust the elevation and azimuth manually to ensure the signal is the main signal.

2.17.4 IMS-1500C Workstation Checks The iMetOS software determines the release by a pressure change algorithm. Position data is determined by where the Telemetry Receiver Antenna is pointing. It should be remembered that the processed data may lag the real-time data by 2 minutes or more.

2.18 Flight Check of the IMS-1500 At the SMC check the following:

• Signal strength – Within 5 minutes after release, the signal strength should typically be above 60 db.

• Received Frequency – The AFC should be set to Auto and the received frequency should be within 5 MHz of what it was during baselining.

• Audio signal – Should sound clear without any noise.

• IMS-1500 tracking motors – Tracking motors on and the angular data display must be showing changing angular values.

• Elevation angles – If angles exceed 80 degrees, follow the procedures for handling overhead balloon flight conditions.

• Tracking mode – Should be set to the Auto mode. However, if the flight is overhead leave the tracking in Manual until the elevation angle drops below 60 degrees.

2.19 Corrective Actions If the signal strength is weak or noisy, or there is a major shift in the radiosonde frequency, there is either a problem with the radiosonde or ground equipment. Sometimes these problems will go away as the flight progresses or they get worse possibly resulting in the termination of the flight due to missing or bad data. If the observer notices these or similar problems check the following:

• The actual time and date for the observation can be misleading. When releases are made 30 minutes or longer prior to standard release time the iMetOS will give the hourly time for coded messages as 0000Z or 1200Z.

• Occasionally the tropopause level is not in the coded message but it is displayed in the standard level report. The observer must be alert to this omission and manually insert the tropopause data into the coded message.

• Occasionally the maximum wind level is not in the coded message but it is displayed in the standard level report. The observer must insert the maximum wind level in the coded message.

• Occasionally after the balloon has burst and is falling but still transmitting data, the incoming data will replace the existing data for the maximum wind. Stay alert for this and make the necessary corrections.

• Make sure the IMS-1500C equipment is not tracking a "side lobe". If it is determined side lobe tracking is occurring, set the tracking mode to Manual. Gradually adjust the elevation and azimuth angles (7 degrees on each side) until a significant increase in



signal strength occurs. Reset the tracking mode to Auto Tracking.

• Check the elevation angle. If it is over 80 degrees follow the procedures in Section 2.20.

• Check the radiosonde frequency. If the frequency shift becomes so severe that the IMS-1500C AFC Mode ON can not find or track the radiosonde signal, try setting the AFC Mode to OFF and sweep the frequency until it locks onto the radiosonde. Reset the AFC Mode to ON.

• Closely monitor the flight data until the flight train reaches at least 400 hPa.

• If problems persist from one flight to the next, there may be problems with the ground equipment or the way the radiosonde is prepared and/or how the flight train is released (e.g., rapid shift in frequency may be a result of a poorly prepared/handled radiosonde). If it is determined that the observer’s actions are not a cause for the problems, the station Electronics Technician should check the equipment.

2.20 Balloon Overhead In a situation where the balloon appears to be likely to go overhead with the IMS-1500C tracking equipment, the observer should closely monitor the elevation and azimuth angles. If the balloon appears to be going overhead, the operator should press the “Tracking Mode - Manual” indicator and manually position the antenna using the past observed movements to determine the trend and which direction the instrument is tracking. This condition may require some delicate adjustment, but once the signal strength is regained go back into “Tracking Mode – Auto”.

2.21 Failed Flight Flights are deemed a failure if one or more of the following occurs:

• The balloon fails before reaching 400 hPa.

• The amount of missing temperature data exceeds 4 minutes between surface and 700 hPa and 6 minutes from surface and 400 hPa.

• The quality and accuracy of the pressure and/or temperature data are deemed poor by the software or by the observer.

• Do not attempt a second release if the problem that caused the flight failure cannot be corrected or mitigated before the next release is made.

• Always follow the local requirements for second or third release.

2.21.1 No Data above Surface Available If a flight fails at release and no data above surface is available, the observer should manually code the TTAA, TTBB, and TTDD messages. The TTCC message does not need to be sent. Example: The following code groups would be sent for flight equipment failure at (Curacao) 78988. TTAA 60121 78988 51515 10142= TTBB 60121 78988 51515 10142= TTDD 60121 78988 51515 10142=



2.21.2 Data above Surface Available A successful flight normally requires an ascent to 400 hPa, however if upper-air data above the surface is obtained and a second release is not possible the data acquired should be used. The flight must be assigned an ascent number and archived if the data is transmitted

2.22 Data Checks High quality upper-air observations are critical for Hurricane and normal operations. The IMS-1500C or any other Upper-air ground Systems are expected to eliminate the observer’s requirement to edit and correct data. Checking the quality and plausibility and then editing the upper-air data are essential part of an upper-air observer. The observer must make every effort to identify and edit erroneous data before it is disseminated.

2.23 Deadlines for Transmission of Observation Once the observer has checked the quality of the data, transmit the coded messages. These data shall be transmitted through the telecommunications system in as timely a manner as possible. Failure to transmit the observation on time will result in the data not being ingested into one or all of the numerical weather prediction models.

2.23.1 Deadlines for Transmitting Coded Messages The deadlines for transmitting the coded messages are shown in Table 2-4. When some data are available but a full report cannot be filed (because of late release, etc.) a partial report shall be transmitted within the time scheduled for a full report.

Table 2-4: Deadlines for Transmitting Upper-air Data Part A: H + 30 minutes Part B: H + 30 minutes Part C: H + 120 minutes

On a typical flight lasting 100 minutes, the Part A and B messages are ready for transmission at about H + 15 minutes ( H is the time at either 00:00 or 12:00 UTC) and the Part C and D messages are ready at about H + 40 minutes. If the observer has other office duties to perform away from the IMS-1500C computer, the data should be checked and transmitted at the above times. It is very important that all standard flights between H-60 and H+29 have the GG (indicated UTC) of 00Z or 12Z. The InterMet Operating System (iMetOS) allows for early release between H-60 and H-29). The observer shall check the TTAA, TTBB, PPBB, TTCC, TTDD, and PPDD messages for the correct scheduled release time in the YYGGId. The only exception to this rule is in the TTBB message code group (8GGgg). This group shall retain the actual release time.

2.24 Coded Message Coded messages may be manually generated anytime during the flight. The iMetOS software will code WMO coded messages whenever the Temp-1 or Temp-2 Message is selected from the reports menu or on the toolbar.



Figure 2-16: TEMP-1

Figure 2-17: TEMP-2



2.24.1 Significant Thermodynamic Levels Parts TTBB and TTDD The reported significant levels alone shall make it possible to reconstruct the air temperature and relative humidity profiles within the limits of the criteria specified. (WMO Manual on codes number 306, Paragraph 35.3.1.1.) Levels which are necessary to ensure that the temperature obtained by linear interpolation (on a T-log P or essentially similar diagram) between adjacent significant levels shall not depart from the observed temperature by more than 1 degree C below the first significant level reported above the 300-hPa level or the first tropopause, whichever, level is the lower, or by more than 2 degrees C thereafter. (WMO Manual on codes 306, Paragraph 35.3.1.3.a) Levels which are necessary to ensure that the relative humidity obtained by linear interpolation between adjacent significant levels shall not depart by more than 15 percent from the observed values. (The criterion of 15 percent refers to an amount of relative humidity and not to the percentage of the observed value e.g., if an observed value is 50 percent, the interpolated value shall lie between 35 percent and 65 percent). (WMO Manual on codes 306, Paragraph 35.3.1.3.b)

2.24.2 Significant Winds Levels parts PPBB and PPDD The reported significant data alone shall make it possible to reconstruct the wind profile with sufficient accuracy for practical use. Care shall be taken that:

(a) The direction and speed curves (as a function of the log of pressure or altitude) can be reproduced with their prominent characteristics.

(b) These curves can be produced with an accuracy of at least 10 degrees for direction and 5 meters per second for speed.

(c) The number of significant levels is kept strictly to a necessary minimum. To satisfy these criteria, the following method of successive approximation is recommended, but other methods of obtaining equivalent results may suit some national practices better and may be used:

1. The surface level and the highest level attained by the sounding constitute the first and the last significant levels. The deviation from the linearly interpolated values between these two levels is then considered. If no direction deviates by more than 10 degrees and no speed by more than 5 meters per second, no other significant levels need be reported. When one parameter deviates by more than the limit specified in paragraph (b) above, the level of greatest deviation becomes a supplementary significant level for both parameters.

2. The additional significant levels so introduced divide the sounding into two layers. In each separate layer, the deviations from the linearly interpolated values between the base and the top are then considered. The process used in paragraph (1) above is repeated and yields other significant levels. These additional levels in turn modify the layer distribution, and the method is applied again until any level is approximated to the above mentioned specified values.

2.24.3 Missing Wind Data If altitude is given in geopotential units in Parts B of D, a layer for which data are missing shall be indicated by reporting the boundary levels of the layer and a level in between with a height value somewhere in between the boundary heights and a group ddfff or solidi (/////) to indicate



the layer of missing data, provided that the layer is at least 1500 geopotential meters thick. The boundary levels are the levels closest to the bottom and the top of the layer for which the observed data are available. The boundary levels are not required to meet “significant level” criteria. (WMO Manual on codes number 306, Paragraph 32.3.1.5.1).

2.25 WMO Abbreviated Heading The structure and meaning of the alpha and numeric characters of the WMO abbreviated heading ( "COMMS" header, as it is called) is outlined here for a better understanding of how the abbreviated heading is built and what the character designators that make up the heading represent. The WMO abbreviated heading is a component of the WMO Meteorological message agreed by WMO members for use in exchanging data and products on the Global Telecommunication System between National Meteorological Centers of the world. (See the documentation on the GTS on this web site.) The structure of the heading is briefly outlined to provide for a better understanding of the meaning implied in the communications abbreviated heading. The heading does define data content through character designators contained in the WMO & U.S. National Practice "tables" that are used to construct the heading. This is a limited definition of content for transmission management only. Those pages from the WMO Manual on the Global Telecommunication System, No. 386; and the U.S. national practice tables are provided on this web site to help in understanding the structure of the heading. The published WMO Manual No. 386 contains the complete technical description of the WMO meteorological message. (Refer to our WMO web page for how to obtain WMO manuals)

2.25.1 WMO Abbreviated Heading T1T2A1A2ii CCCC YYGGgg T1T2A1A2ii DATA DESIGNATORS

T1T2 DATA TYPE and/or FORM DESIGNATORS A1A2 GEOGRAPHICAL and/or DATA TYPE and/or TIME DESIGNATORS Ii Always 01

CCCC International four-letter location indicator of the station. YYGGgg International date-time group

YY day of month GGgg Standard time of Observations (0000 or 1200) for scheduled observations.

T1T2A1A2 ii characters for CHUAS are defined by WMO Manual 386. T1T2

US = Upper-level pressure, temperature, humidity & wind (Part A) UK = Upper-level pressure, temperature, humidity & wind (Part B) UG = Upper-wind (PPBB) UL = Upper-level pressure, temperature, humidity & wind (Part C) UE = Upper-level pressure, temperature, humidity & wind (Part D) UQ = Upper-wind (PPDD)



A1A2

(See table below) ii Always “01” The CCCC is the location identifier of origin of the bulletin (ICAO Call Sign).

STATION NAME A1A2 CCCC Bahamas BA MYNN Barbados BR TBPB Belize BH MZBZ Curacao NU TNCC Dom. Republic DR MDSD Grand Cayman GC MWCR Jamaica JM MKJP San Andres CO SKSP St. Maarten MN TNCM Trinidad TD TTPP

2.26 Coded Message Breakdown The observer must understand how to properly code and decode upper-air messages. The messages for the sites in the continental United States, Alaska, the Bahamas, and the Caribbean are in WMO Region IV. 91285 TTAA 56001 91285 99011 28060 01009 00107 24856 01007 92787 20456 33502 85514 18265 22504 70145 07413 27011 50586 04170 33025 40758 17367 32025 30966 32764 30537 25092 40762 30545 20241 52560 30541 15421 67158 30024 10657 79756 32024 88999 77999 31313 05102 82307 51515 10164 00011 10194 32003 23507= IIiii TTAA YYGGId IIiii 99PPP TTTDD ddfff 00hhh TTTDD ddfff 92hhh TTTDD ddfff 85hhh TTTDD ddfff 70hhh TTTDD ddfff 50hhh TTTDD ddfff 40hhh TTTDD ddfff 30hhh TTTDD ddfff 25hhh TTTDD ddfff 20hhh TTTDD ddfff 15hhh TTTDD ddfff 10hhh TTTDD ddfff 88PPP 77PPP 31313 sr rara sasa 8GGgg 51515 10164 000IsIs 10194 ddfff ddfff= NOTE: IIiii – First Block number and station number may not appear on The SMC, but will be added to the message by NCEP. TTAA - Indicator of mandatory levels up to 100 hPa. YYGGId - YY - Day of the month, (When winds are given in knots 50 will be added to YY) GG - Actual time of observation, to the nearest whole hour UTC



Id - Indicator used to specify the pressure relative to the last standard isobaric surface for which a wind is reported. Reported to the nearest hundreds of Hectopascal (Used in TTAA and TTCC) PPhhh - Mandatory pressure levels PP - Starts with 99 - indicating surface 00 -1000 hPa 92- 925 hPa 85 - 850 hPa on until 10 - 100 hPa. hhh - Height in geopotential meters (gpm) Sfc to 500 hPa - Reported in whole gpm (thousands not reported) 3204 gpm reported 204 500 hPa to Term - Reported in tens of gpm 6053 gpm reported 605 TTTDD - Temperature and Dewpoint Depression Values TTT - Dry bulb temperature in degrees Celsius. Last digit indicates if the temperature is negative or positive. Negative temperatures will have an odd number for the 3rd digit. Positive temperatures will have an even number for the last digit. DD - Dewpoint depression. This number is subtracted from the dry bulb temperature. Numbers of less than 55 are degrees and tenths. (i.e) 49 is 4.9 degree dewpoint depression. Numbers of 56 or greater are dewpoint depressions in whole degrees. To obtain the proper dewpoint depression value subtract 50 from any value 56 or greater. (i.e) 72 would be a dewpoint depression of 22 degrees. ddfff - Wind Direction and Speed dd - True wind direction to the nearest 10 degrees. Wind directions of 500 degrees or greater indicate winds with speeds greater than 100 knots. When reading the direction in this case, one should subtract 500 from the direction and remember to add 100 to the wind speed value. fff - Wind speed in knots. Wind directions are actually rounded to the nearest 5 degrees. The unit digit of the wind direction is added to the hundreds digit of the wind speed. (i.e., 27520 is winds from 275 degrees at 20 knots.) 88PPP - TTTDD ddfff 88 - indicates tropopause 77PmPmPm - ddfff 77 - indicates max wind group

When a maximum wind occurred within the sounding and its level was determined by means of pressure, the indicator figures 77 shall be used in the first group of Section 3, i.e. 77PmPmPm.

51515 - Regional Code Groups Follow 10164 - Indicator for the stability index that follows 10194 - Indicator that the mean low level wind groups follow ddfff ddfff - First group mean winds sfc - 5000 feet Second group mean winds 5000 - 10000 feet



= (End of message symbol) It is a telecommunications character and is not part of the code. 91285 TTBB 56000 91285 00011 28060 11008 26057 22000 24856 33905 19057 44850 18265 55795 13257 66768 12260 77764 12039 88700 07413 99679 05817 11675 06259 22670 06661 33652 06061 44644 05666 55627 03462 66606 02068 77567 01163 88548 01271 99478 05769 11339 28364 22281 34763 33137 71358 44100 79756 31313 05102 82307 41414 59571= IIiii TTBB YYGGa4 IIiii 00PPP TTTDD 11PPP TTTDD 22PPP TTTDD 33PPP TTTDD 44PPP TTTDD 55PPP TTTDD 66PPP TTTDD 77PPP TTTDD 88PPP TTTDD 99PPP TTTDD 11PPP TTTDD 22PPP TTTDD 33PPP TTTDD 44PPP TTTDD 55PPP TTTDD 66PPP TTTDD 77PPP TTTDD 88PPP TTTDD 99PPP TTTDD 11PPP TTTDD 22PPP TTTDD 33PPP TTTDD 44PPP TTTDD 31313 sr rara sasa 8GGgg 41414 NhCLhCMCH= a4 - Type of measuring equipment used

0 - Pressure instrument associated with wind-measuring equipment (B2) 1 - Optical theodolite 2 - Radiotheodolite 3 - Radar 4 - Pressure instrument associated with wind-measuring equipment but pressure element failed during ascent 5 - VLF-Omega 6 - Loran-C 7 - Wind profiler 8 - Satellite navigation 9 - Reserved

PPP - Pressure of Significant Levels Selected SFC to 100 hPa - Levels selected to nearest whole hPa Above 100 hPa - Levels selected to nearest 0.1 hPa 31313 - Data on Temp & Sounding System Used

sr - Solar and infrared radiation correction for CHUAS “0”

0 - No correction 1 - Correction Made

rara - Radiosonde Used for CHUAS “51”

87 - Sippican GPS Mark II (USA) 51 - Sippican type B-2 52 - Vaisala RS80-57 (Finland)

sasa -Tracking Technique/Status Used for CHUAS “02”



00 - No windfinding 01 - Automatic with auxiliary optical direction finding 02 - Automatic with auxiliary radio direction finding (IMS-1500C) 03 - Automatic with auxiliary ranging 05 - Automatic with multiple VLF-Omega frequencies 06 - Automatic cross chain Loran-C 07 - Automatic with auxiliary wind profiler 08 - Automatic satellite navigation

8 - Indicator

GG - Hour UTC of release gg - Minute of release

41414 - Cloud Data NhCLhCMCH

Nh - Amount in eighths of all the CL present or, if no CL is present, the amount of all the CM

present. CL - Type of low cloud present h - Height above surface of lowest cloud seen CM - Type of middle cloud present CH - Type of high cloud present

PPBB 56000 91285 90012 01009 01003 00502 90346 32002 26003 20502 90789 21005 23508 27013 91245 26512 27016 26514 9169/ 31013 33026 9205/ 32523 32025 93013 31034 31538 29542 935// 30547 949// 30024 9504/ 30025 32037= PPBB YYGGa4 Iiiii 9tnuuu ddfff ddfff ddfff 9tnuuu ddfff ddfff ddfff= YYGGa4 Iiiii ddfff - Previously described

9 - Indicator to show winds in units or 300 meters or 1,000 foot increments tn - Indicates tens digit of altitude – (0 = less than 10,000 feet) (1 = 10,000 - 19,000 feet) u - Indicates the unit value of altitude of winds

91285 TTCC 56000 91285 70858 76757 05508 50059 63959 11005 30378 54160 06009 20638 51161 07512 88922 82356 33014 77999 31313 05102 82307= TTDD 56000 91285 11922 82356 22700 76757 33517 64359 44472 64959 55364 57560 66130 47162 31313 05102 82307= PPDD 56000 91285 9556/ 32522 33015 970// 13004 98047 08012 09512 07012 99015 08012 08011 05005=



2.26.1 Standard Atmosphere Heights Standard Heights of Isobaric Surfaces are shown in Table 2-5.

Table 2-5: Standard Atmosphere Heights Standard Surface hPa

PnPn Coded as

Approximate Height m

hnhnhn Coded as

1000 00 100 100 925 92 750 750 850 85 1500 500 700 70 3000 000 500 50 5600 560 400 40 7200 720 300 30 9200 920 250 25 10400 040 200 20 11800 180 150 15 13600 360 100 10 16200 620 70 70 18500 850 50 50 20600 060 30 30 23900 390 20 20 26500 650 10 10 31100 110 7 07 33400 340 5 05 35800 580 3 03 39400 940 2 02 42400 240 1 01 47800 780

2.26.2 Fixed Levels for Reporting Purposes

Wind directions and speeds, when they are available, shall be selected on the basis of the altitudes of the fixed levels listed in Table 2-6

Table 2-6: Altitude of the Fixed Wind Levels Feet Meters Feet Meters Feet Meters 1,000 300 12,000 3,600 70,000 21,000 2,000 600 14,000 4,200 80,000 24,000 3,000 900 16,000 4,800 90,000 27,000 4,000 1,200 20,000 6,000 100,000 30,000 6,000 1,800 25,000 7,500 110,000 33,000 7,000 2,100 30,000 9,000 8,000 2,400 50,000 15,000 9,000 2,700 60,000 18,000

Breakdown for 101AdfAdf - Miscellaneous Regional Data Code Figure Definition



40 - 59 Reason for no report or an incomplete report 40 Report not filed 41 Incomplete report; full report to follow 42 Ground equipment failure 43 Observation delayed 44 Power failure 45 Unfavorable weather conditions 46 Low maximum altitude (less than 1500 feet above ground) 47 Leaking balloon 48 Ascent not authorized for this period 49 Alert 50 Ascent did not extend above 400 hPa level 51 Balloon forced down by icing conditions 53 Atmospheric interference 54 Local interference 55 Fading signal* 56 Weak signal* 57 Preventive maintenance 58 Flight equipment failure (transmitter, balloon, attachments, etc.) 59 Any reason not listed above * Fading signals differ from weak signals in that "fading signals" are first received satisfactorily, then become increasingly weaker, and finally become too weak for reception, while "weak signals" are weak from the beginning of the ascent. 60 - 64: Miscellaneous 62 Radiosonde report precedes 64 Stability index follows: 000IsIs 65 - 69: Doubtful Data 65 Geopotential and temperature data are doubtful between following levels: 0PnPnP'nP'n

66 Geopotential data are doubtful between the following levels: 0PnPnP'nP'n

67 Temperature data are doubtful between the following levels: 0PnPnP'nP'n

68 Dew point depression is missing between the following levels: 0PnPnP'nP'n (not used when TnTn is also missing) 70 - 74 Not allocated 75 - 89 Corrected Data 78 Corrected tropopause data section follows 79 Corrected maximum wind section follows 80 Corrected report for the entire report (first* and second* transmissions) follows 81 Corrected report of the entire PART A and/or PART B precedes 82 Corrected report of the entire PART C and/or PART D precedes 83 Corrected data for mandatory levels** follow 84 Corrected data for significant levels** follow 85 Minor error(s) in this report; correction follows 86 Significant level(s) not included in original report follow: //PnPnPn

TnTnTanDnDn or PnPnPnTnTn



87 Corrected data for surface follow 88 Corrected additional data groups follow: 101AdfAdf....etc. 90 - 99 90 Extrapolated geopotential data follow: PnPnhnhnhn (dndndnfnfn) 94 Averaged wind for the surface to 5000 foot MSL layer and the 5000 to 10000 foot MSL layer follows: ddfff ddfff (can be used in the PART A message) NOTE: Numbers not shown have no assigned meaning or do not pertain to NWS upper-air sites. Unless both the stability index and the mean winds are missing, the Part A message always contains two special 101 groups as follows: 10164 Group that identifies stability index. 10194 Group that identifies the mean winds. A 5-character group 000IsIs follows the 10164 which contains the encoded stability index. The IsIs value that appears in the coded message for the stability index is interpreted as follows:

Table 2-7: Stability Index

Code Value Meaning 00 to 40 Stability index is 0 to 40 51 to 90 Stability index is -1 to -40 91 RH <20% at either base or 500 mb level or calculation

failed 92 RH is missing at the base level

The 10194 group for mean winds from the surface to 5000 feet MSL and from 5000 to 10000 feet MSL are encoded in two code groups using the format dmdmfmfmfm, where dmdm is the mean direction and fmfmfm is the mean wind speed. If the mean wind is missing, it is reported as /////. If winds for both layers (i.e. Sfc. - 5K and 5K to 10K feet MSL) are missing, the 10194 is not sent. Additional 101 groups as shown in the Table can be entered after the 51515 as long as the last two digits are in ascending order with the other groups. For example, if the report has been corrected, this section would appear as follows: 51515 10164 00092 10181 10194 ///// 26516=

2.27 Terminating the Observation This section discusses flight termination procedures and data archiving. It is important to remember that these tasks should be done after reviewing the data. The observer shall determine the point of termination, termination reason, and that all data is accurate and should be archived. The software can not select the correct reason for termination for every occasion.



The observer shall verify the accuracy of the flight data throughout the flight, prior to transmission and again prior to data archiving.

2.28 Termination The three common reasons an observation is terminated are:

1. Balloon burst: Nearly all flights terminate due to balloon burst. A plot of pressure versus time will show a change to increasing atmospheric pressure values. The system detects this and initiates an automatic termination.

2. Floating balloon: The system can detect the signal trend characteristics of a floating balloon (i.e., nearly constant altitude). The software will normally terminate the observation.

3. Weak or fading signals: Missing data results when radiosonde signals become weak or fade in and out. If this continues the system will terminate the observation.

2.28.1 Automatic Termination When the observation is automatically terminated, the observer must look at the data to decide if the reason for termination and point of termination selected is correct. It is important to check all data for correctness before transmitting any coded messages. The observer should always go into the “MET” and “POSITION” data and look to see that the flight was terminated at the right point. One should look for:

1. Realistic ascension rates - No balloon should ascend faster than 500 meters/minute. Check the heights in the “MET” data and compare the heights at different times and dividing the height difference by the minutes between the heights selected.

2. Realistic “Pressure vs. Time” plot - There should be no abrupt changes in the pressure profile prior to termination. If a failed or leaking pressure cell is detected by a flattening out of the plot or if there is an abrupt jump in the plot terminate the flight prior to the occurrence.

1. No duplicate levels at or near the termination point - The observer should check the last level and the level preceding it to ensure there is at least 0.1 hPa difference in the values. If there is a duplicate level, the last level should be deleted.

The observer can then edit and transmit the coded messages.

2.28.2 Manual Termination A flight may reach a point where it should be terminated, but SMC has not terminated the flight. In such cased the observation should be terminated manually. If ending flight before balloon burst is desired for any reason, press Stop Flight button on Flight Screen to stop flight processing.

2.29 Archiving the Flight Archiving allows the user to store IMetOS flight files in a single, compressed file. A normal two hour flight takes approximately 1.5 megabytes to store when not compressed. A typical archived (compressed) flight consumes 400-500 kilobytes of disk space. Archive the flight as follows:



a. From the iMetOS menu bar, go to Utilities | Store Files.

b. Change the “To” directory to C:\IMS\iMetOS\Archives.

1) Double click on [..]: c:\ims\imetos

2) Double click on archives: c:\ims\imetos\archive

c. Change the “From” directory to C:\IMS\iMetOS\Flights. (should already be this directory)

d. Select the flight file name in the “File Name” box (flight ascension number). NOTE: If you double click the ascension number the flight will archive to the “TO” directive.

e. Or Click “Archive”.

f. Click “Cancel” after the Command Prompt window automatically closes. The iMetOS will archive the InterMet files as follows:

(.PRB) This file and the RTX file required for recompute

(.PYS) Physical Values

(.RTX) RTX file contains all the raw data from the radiosonde and the antenna. It is the file that InterMet request when the sites have trouble getting sonde data or tracking a sonde. It has detailed information on what the sonde and antenna is doing. It’s also the file that is used to simulate or play back a previous flight.

(.SIG) Significant Levels

(.STD) Standard hPa levels

(.TP1) First Transmission (TTAA ), (TTBB), and (PPBB)

(.TP2) Second Transmission (TTCC), (TTDD) and (PPDD)

1) Once all tasks regarding the flight are complete, the iMetOS may be closed and the flight files may be deleted from the C:\IMS\iMetOS\Flights directory.

2) Make sure Flight has been archived in c:\ims\imetos\archive before deleting from flight directory.

2.30 NWS Archived Files

NOTE: The iMetOS will automatically archive the NWS files (.HDR, .DAT, and .HRS) to the

designated directive (c:\upperair\2008\nov). The directive Year and Month is changed automatically in iMetOS.

The iMetOS will change file name of the NWS files to H, T, and R with the three digit ascension number for the flight. The File Extension is automatically removed from NWS files prior to archiving (See WMO Reports Selection Screen).

(.HDR) NWS Identification Record NWS renamed the “H” (plus ASC #) file

(.DAT) NWS Data Record NWS renamed the “T” (Plus ASC #) file

(.HRS) NWS High Resolution Record NWS renamed the “R” (Plus ASC #) file



2.31 Monthly Special Problems Archival Data shall be archived at the end of each flight. Any flight with special problems shall have the standard archive files saved on diskettes and set aside for further evaluation. Send the monthly special archival files to the NWS Upper-Air Program Office for further evaluation, a copy of the calibration data file and a statement of what happened along with pertinent plots to help illustrate the problem. Send Data to: National Weather Service Headquarters 1325 East-West Highway SSMC2, Room 16368 (attn: Kenneth Clark) Silver Spring, MD 20910

2.32 Shutdown Procedures To exit system, press Exit from File menu of toolbar


Revision B June 2009 3-1 iMetOS

CHAPTER 3

INTERMET METEOROLOGICAL OPERATING SYSTEM (iMetOS)

3.1 Introduction The InterMet Meteorological Operating System (iMetOS) provides operator control of the receiver, radiosonde decoder functions, recording and processing of data transmitted by the, and generation of operator-selected meteorological data, messages and graphs in real time during and/or after flight. An additional function of the iMetOS is playback of flights from previously recorded data files.

3.2 Modes of Operation The iMetOS modes of operation are:

Real Flight: This option is intended for launch of an actual radiosonde. Real flight is described in Chapter 2.

Simulated Flight: This option is intended for playback of a previously implemented flight (for training or data analysis purposes). The procedure for simulated flights is described in Section Error! Reference source not found..

All operations directly related to radiosonde flights (preflight, in-flight and post-flight) are discussed in this chapter, including report and message generation, graph generation, and viewing of reports and messages. System Setup is discussed in Chapter 5.

3.3 Log Files The iMetOS utilizes two different types of log files to record flight data: a raw log file and a processed log file.

3.3.1 Raw Log File The raw log file (*.RTX) contains a log of the communications between the iMetOS and the devices used for the real flight. This file is necessary to view a simulated flight. A record is recorded when data is received from each device that the iMetOS is communicating with. Each record is recorded as received with a space separated PC time field appended to the end. The iMetOS uses the raw log file to play back a simulated flight. Any edited data from before will then be lost, as the iMetOS will create a new processed log file. Some lines will change in format depending on the radiosonde type and receiving antenna used for the flight.

3.3.2 Processed Log File The processed log file (*.LOG) contains the smoothed data and, if the user performs any data editing, edited data. The contents of this file are what the iMetOS uses to generate the met reports and graphs. The log file contains thirteen space separated ASCII fields. Each record is at a one second time increment. The iMetOS uses the processed log file to generate the reports and graphs. If a user edits the


iMetOS 3-2 June 2009 Revision B

data, only the processed log file will be changed. Simulating the flight will cause the iMetOS to create a new processed log file from the raw log file, losing any edits to the data previously performed. To create reports and graphs without simulating the flight, the user should simply use the File → Load Log menu item.

Table 3-1: iMetOS Processed Log File Column Definitions

Column Description Units 1 Temperature Degrees Celsius (°C) 2 Temperature Degrees Kelvin (K) 3 Relative Humidity Percent (%) 4 Pressure Millibars (mbar) 5 Altitude Meters (m) 6 Elevation Angle Should always be zero 7 Azimuth Angle Should always be zero 8 Wind Direction Radians 9 Wind Speed Knots 10 Slant Range Meters (m) 11 Status Flags N/A 12 Latitude Degrees (°) 13 Longitude Degrees (°)

3.4 iMetOS Flight Screen The IMS-1500C System Meteorological Computer software runs under Microsoft Operating System and utilizes all standard Windows function and screen design concepts. The Flight Screen (See Figure 3-1), which is the principal screen for iMetOS operations, is a typical menu driven Windows screen. The title bar, at the top of the screen, gives the name of the meteorological system. The menu bar, immediately below the title bar, lists the additional functions available from the Flight Screen: File, Preflight, Reports, Graph, View, Utilities, Setup, and Help. Reports, graphs, etc. selected by means of the menu bar or toolbar are displayed as panes superimposed on the Flight Screen and may be sized as desired by using the mouse. More than one report/graph may be displayed as individual windows.



Figure 3-1: Flight Screen

3.4.1 iMetOS Menu Bar

3.4.1.1 File

This menu enables creation of a new file (for a new real flight, provided that there is no real or simulated flight in progress), opening of a sonde parameters flight file (for a simulated flight, provided that there is no real or simulated flight in progress), loading of a log file (for viewing reports and graphs of a previously performed flight), and exit from the program.

3.4.1.2 Preflight

This menu enables entry and modification of preflight data (for a new real flight) or review and editing of previously entered preflight data (prior to release) and loading of calibration data, including the Sippican B2 sonde.

3.4.1.3 Reports

This menu enables generation of meteorological reports and messages, for a real or simulated flight in progress or after termination, according to a list of reports selected as part of the system setup. The report output device and WMO indicator are also set through the Reports menu.

3.4.1.4 Graphs

This menu enables generation of PTU graph, winds graph or tephigram (T/log P graph), PTU vs. height graph, density vs. height graph, skew-T log-P graph and stuve graph, for a real or



simulated flight in progress or after termination or a previously implemented flight.

3.4.1.5 View

This menu allows for viewing of reports and messages. Reports can be called up during or after completion of a flight. Other View menu functions include:

− Location in Lat/Lon (UTM): when selected, location will be displayed in degrees; if unchecked, location will be displayed in UTM coordinates

− Angles in Mils (Degrees): when selected, angles will be displayed in mils; otherwise, degrees

− Pressure in hPa (mb): when selected, pressure will be displayed in hPa; otherwise, millibars

− Height in Meters (Feet): when selected, height will be displayed in meters; otherwise, feet

− Temperature in °C (K): when selected, temperature will be displayed in degrees Celsius; otherwise, Kelvin

− Wind Speed in Knots (m/s): when selected, wind speed will be displayed in knots; otherwise, meters per second

− 2D Slant Range (3D): when selected, the slant range will be the horizontal distance (along the ground) to the radiosonde’s location; otherwise, it will be the straight-line distance between the receiving antenna and radiosonde.

3.4.1.6 Utilities

This menu enables performance of various utility operations (see Chapter 4)

3.4.1.7 Setup

This menu enables performance of system setup (see Chapter 5)

3.4.1.8 Help

3.4.2 iMetOS Toolbar The toolbar, immediately below the menu bar, enables "one-touch" rapid performance of the following frequently implemented operations.

3.4.2.1 New

This button enables creation of a new file (for a new real flight, provided that there is no real or simulated flight in progress).

3.4.2.2 Open

This button enables opening of a sonde parameters flight file (for a simulated flight, provided that there is no real or simulated flight in progress).

3.4.2.3 Load Log

This button enables loading of a log file (for viewing reports and graphs of a previously performed flight, provided that there is no real or simulated flight in progress).

3.4.2.4 Preflight

This button enables entry and modification of preflight data (for a new real flight) or review and editing of previously entered preflight data (for a simulated flight).



3.4.2.5 Report 1, 2 11, and 12

These buttons enable generation of the first two WMO reports (TEMP-1, TEMP-2), Standard Levels and the Significant Levels selected as part of the system setup, for a real or simulated flight in progress or after termination.

3.4.2.6 PTU, Wind, T/P

These buttons enable generation of PTU graph, winds graph and tephigram (T/log P graph), respectively, for a real or simulated flight in progress or after termination, or a previously implemented flight.

3.4.2.7 Reports and Messages

These buttons enables viewing standard levels report for a previously implemented flight.

3.4.2.8 Physical Values

This button enables viewing of physical values report for flight in progress.

3.4.2.9 Exit

This button enables exit from system (provided that there is no real or simulated flight in progress).

3.4.2.10 Map Scale

This pulldown menu enables selection of a map scale for the radial radiosonde plots. Allowable values include AUTO, 1 km, 2 km, 5 km, 10 km, 20 km, 50 km, 100 km, 200 km, and 500 km.

3.4.2.11 Change Sonde Type

This button enables selection of radiosonde type from pull down list (provided that there is no real or simulated flight in progress). If there is a real or simulated flight in progress, selecting another sonde type will not have any effect. Reports, graphs, and (etc.) selected by means of the menu bar or toolbar are displayed as panes superimposed on the Flight Screen and may be sized as desired by using the mouse. More than one report/graph may be displayed at one time.

3.4.3 iMetOS Status Bar The status bar, at the bottom of the screen, shows the operation mode (Real Flight or Simulated Flight), flight status (FLIGHT NOT READY, FLIGHT READY, and FLIGHT IN PROGRESS), the date, local time and possibly also GMT time (if selected in System Setup).

3.4.4 Flight Screen Main Body The main body of the Flight Screen consists of three main areas (receiver, antenna, and telemetry).



3.4.4.1 Receiver Area

Figure 3-2: Receiver Area

The receiver area, at the top left of screen, displays receiver operating parameters in the following format: − Signal level: analog format (length of line along a vertical scale in dBm)

− Receiver tuned frequency: analog (position of signal level line along a horizontal scale in MHz) and digital format

− Receiver frequency sweep speed (fast/medium/slow): adjust the frequency step size when the frequency slew buttons are pressed

− AFC ON/OFF: click button

NOTE: The following two selections are disabled if the receiver is in automatic frequency

control (AFC) mode.

− Receiver frequency search: activate a one time search for the maximum signal strength; receiver will automatically tune to greatest signal strength found when complete

− Receiver frequency slew: click up or down buttons to adjust the receiver’s tuned frequency

NOTE: As the transmission frequency weakens during the flight, the AFC will automatically

be switched off to prevent the receiver from searching for a stronger signal. This can also happen if the sonde is directly overhead and the transmission is weakened by the “null” of the UHF antenna. In either case, the system will switch AFC on and off to maximize reception. This is a normal condition and does not indicate a system malfunction.



3.4.4.2 Radiosonde Area

Figure 3-3: Radiosonde Area

The radiosonde area displays radiosonde data in the following format:

− Radiosonde horizontal track: a plot of the relative horizontal path of the radiosonde with the position given by a yellow dot

− Radiosonde vertical track: a plot of the relative vertical path of the radiosonde with the position given by a yellow dot

− The Sim Speed control adjusts the speed of flight simulations when replaying previously recorded flights.

3.4.4.3 Telemetry Area

Figure 3-4: Telemetry Area

The telemetry area, at the bottom of the screen, displays the following flight parameters in digital format only: − Record number − Flight clock



− Radiosonde ID − PTU − Height (above sea-level) − Slant range - the distance between the receiving antenna and radiosonde − Latitude (base station only until radiosonde reports GPS data) − Longitude (base station only until radiosonde reports GPS data) − Wind direction − Wind speed − Ascent rate

3.5 iMetOS Graphs Graphs may be generated for a real or simulated flight in progress or after termination, or for a previous flight with valid data files. The graph cursor may be moved to any desired point on the graph by moving the mouse. A table to the right of the graph, titled "View", displays physical values for point at which the cursor is located, for viewing only.

3.5.1 Graph Menu Bar The menu bar, immediately below the title bar, lists the additional functions available from any of the graph screens: File, Edit, Scale, Zoom, Interpolate and SigPoints − File: enables loading of a log file (for viewing graphs of a previously recorded flight), saving

of a log file (after modification of log file data - see below), printing of the respective graph, and exit from the graph screen

− Edit: enables editing and cutting of graph data − Scale: enables selection of desired pressure scale (1000 - 10 mB, 1000 - 100 mB, 1000 -

500 mB) on PTU and tephigram graphs, and desired wind scale (0° - 360°, 180 - 180°) on winds graph

− Zoom: enables zooming in to pressure level selected by means of cursor, displaying ±10% above/below that level, or zooming out to view the entire graph, on PTU and winds graphs

− Interpolate: enables interpolation of values between two selected points of the graph − SigPoints: enables location, insertion and deletion of significant points relevant to the graph

3.5.2 Graph Toolbar The toolbar, immediately below the menu bar, enables "one-touch" execution of the following frequently implemented operations: − Load log: enables loading of a log file (for viewing graphs of a previously recorded flight) − Save log: enables saving of a log file (after modification of log file data - see below) − Print: enables printing of the respective graph − Cut: enables cutting of a selected portion from graph − Edit: enables editing of a selected point on graph − Pressure Scale: enables selection of desired pressure scale (1000 - 10 mB, 1000 - 100 mB,

1000 - 500 mB) on PTU and tephigram graphs − Wind Scale: enables selection of desired wind scale (0° - 360°, 180 - 180°) on winds graph



− Zoom In: enables zooming in to pressure level selected by means of cursor, displaying ±10% above/below that level, on PTU and winds graphs

− Zoom Out: enables zooming out to view the entire graph, on PTU and winds graphs

3.5.2.1 Editing Data in Graph Mode

To edit physical values data for any point, select Edit Data from Edit menu or press Edit button on toolbar. Bring cursor to desired point on graph (by moving mouse) and click. Screen will display a table of physical values for that point, headed "Edit Physical Values". Edit physical values as desired and press OK. The graph will be updated according to edited physical values. To cut a range of data in any segment of graph which does not appear accurate or which is irrelevant, bring cursor to lower limit of range to be replaced by interpolated data, click, drag cursor to upper limit of range to be replaced by interpolated data, release, and select Cut Data from Edit menu or press Cut button on toolbar. This will delete the data within the selected range from the log file of the respective flight. To interpolate data in any segment of graph which does not appear accurate, bring cursor to lower limit of range to be cut, click, drag cursor to upper limit of range to be cut, release, and select the desired interpolation operation from the Interpolate menu. This will interpolate data for the selected range in the log file of the respective flight. To insert a Significant Point on graph, bring cursor to desired location for significant point insertion, click, and select the desired Insert function from the SigPoints menu. To delete a Significant Point from graph, bring cursor to significant point to be deleted, click, and select the desired Delete function from the SigPoints menu. Any changes made will be saved to the processed log (*.LOG) file, if desired. Simulating the flight will return the data to its original state. To superimpose a graph from another flight, select File from graph menu bar or load log button from graph toolbar; select desired file. Graph from previous flight will appear superimposed on present graph.



3.5.2.2 PTU Graph

Figure 3-5: PTU Graph

The PTU graph is accessed by pressing PTU button on Flight Screen toolbar, and may be sized as desired by means of Microsoft Windows screen controls. As a default, temperature is displayed in red; relative humidity in blue; dew point in green. Pressure standard levels (corresponding to horizontal lines on graph) are displayed in figures at right of screen. For each pressure standard level, the corresponding sonde altitude, wind direction and speed are displayed in figures at left of screen. Top of screen displays graph title, flight start date and time, and the flight reference number.



3.5.2.3 Wind Graph

Figure 3-6: Wind Graph The Winds graph is accessed by pressing WIND button on Flight Screen toolbar, and may be sized as desired by means of Microsoft Windows screen controls. As a default, wind direction is displayed in green; wind speed is displayed in purple. Pressure standard levels (corresponding to horizontal lines on graph) are displayed in figures at right of screen. For each pressure standard level, the corresponding sonde altitude, wind direction and speed are displayed in figures at left of screen. Top of screen displays graph title, flight start date and time, and flight reference number.



3.5.2.4 T/Log P Graph

Figure 3-7: T/Log P Graph

The tephigram is accessed by pressing T/P button on Flight Screen toolbar, and may be sized as desired by means of Microsoft Windows screen controls. As a default, real temperature is displayed in red; dew point as a function of pressure is displayed in green; pressure lines in solid gray; adiabatic lines in dotted gray; mixing ratio in brown. Top of screen displays graph title, date and time, and file number.



3.5.3 Report Generation Partial meteorological messages and reports may be generated at any time after launch in simulated or real flight modes. To enable reports to be displayed, printed or transmitted, select Reports from the Flight Screen menu bar. The following screen will be displayed:

Figure 3-8: Report Generation First select desired output device (default: screen). Select the desired report by means of mouse or indicated function keys. Reports are generated in plain text format and opened using WordPad (included with Windows). Each report generated is saved in a file whose name is composed of the flight reference number (ascension number) and the suffix appropriate to the report type.



Figure 3-9: Standard Levels

Figure 3-10: Significant Levels



Figure 3-11: Physical Values Report

3.5.3.1 Report Menu Bar

The menu bar is a standard Windows menu bar.

3.5.3.2 Report Toolbar

The toolbar is a standard Windows toolbar. To select a portion of the report for editing, bring cursor to upper limit of desired portion (by moving the mouse), click, press SHIFT key on computer keyboard, drag cursor to lower limit of desired portion, release. Now cut or copy marked portion as desired.



3.5.4 Viewing Physical Values

Figure 3-12: View Physical Values

3.5.4.1 Data Interpolation

To interpolate data for a segment of physical values which appears inaccurate, bring cursor to upper limit of range to be replaced by interpolated data, click, press SHIFT key on computer keyboard, drag cursor to lower limit of range to be replaced by interpolated data, release, and select the desired interpolation operation from the Interpolate menu. This will interpolate data for the selected range in the log file of the respective flight.

3.5.5 End of Flight When a balloon burst is detected, the message “BALLOON BURST TERMINATE FLIGHT?” will flash on the screen and audio alarm will sound. Click Yes to stop flight. If ending flight before balloon burst is desired for any reason, press Stop Flight button on Flight Screen to stop flight processing. Screen will display: TERMINATE FLIGHT? To terminate flight, click Yes. When flight has been terminated, FLIGHT NOT READY will be displayed on status bar of Flight Screen.



3.5.6 Exiting the iMetOS To exit from system, press Exit from File menu or toolbar.

3.6 Simulated Flights The simulated flight function can be used to both replay a previously recorded flight or to view its reports and graphs. To view graphs and reports without replaying an entire flight, select Load Log from the File menu on the Flight Screen menu bar, or from the Flight Screen toolbar. Select the desired file name and click Open. The reports and graphs will be accessible as if the flight had been recently terminated. To initiate a simulated flight, open iMetOS and select Simulate Flight. When the Main Flight Screen appears, select Open from File menu on the Flight Screen menu bar, or from the Flight Screen toolbar. Select desired file name and click Open. The Pre-Flight Screen will automatically be displayed, with preflight data for this flight entered. Modify data if desired and click OK. Flight screen will now appear with FLIGHT READY displayed in status bar at bottom of screen. Press the Start Flight button to begin the simulation. The replay speed can be adjusted using the Sim Speed control located on the Main Flight Screen.



3.6.1 Simulated Flight Procedures Press Start Flight to start the recorded flight. Flight data will begin updating as if a real flight was in progress.

Figure 3-13: Simulated Flight

As a default, a simulated flight will proceed at approximately 2 times normal speed. To speed up or pause the simulation, slide the simulation speed bar up to speed up, or down to slow down. The lowest speed is paused. Graphics and reports can be accessed in the same manner as Real Flights.


Revision B June 2009 4-1 Utilities

CHAPTER 4 SMC UTILITIES

4.1 Utilities Menu To access Utilities Menu, select Utilities from Flight Screen menu bar. The following screen will be displayed:

Figure 4-1: Utilities


Utilities 4-2 June 2009 Revision B

4.1.1 Store Files The Store Files (Create Archive) screen appears below:

Figure 4-2: Create Archive

The Store Files (Create Archive) screen appears above when the Store Files menu item is selected from the Utilities menu. An archive contains the necessary files to simulate a flight as well as any reports generated in a compressed format. A 1.5 hour flight would normally take about 1.5 megabytes to store all files separately, but in an archive, generally only takes 400-500 kilobytes. The Create Archive window is broken up into two areas: a FROM area and a TO area. Use the FROM area to choose a FROM directory and a log file. Double click on directories to change directories. Single-click the flight log file to select it. By default, flight files are located in the C:\IMS\iMetOS\Flights directory. Use the TO area to navigate to a directory to place the archived (zipped) file. Notice that the path is given above the TO folders area. Click the Archive button to create the archive. For uniformity, it is recommended that the archived files be placed in the C:\IMS\iMetOS\Archives directory. The iMetOS only archives the products that have been generated. The windows checked as shown in WMO Reports Selection will ensure that the necessary products have been generated and to cover all situations (like early termination) and other unforeseen operations.

4.1.2 Restore Files The Restore Files (Restore from Archive) screen appears below:



Figure 4-3: Restore from Archive

To restore previously recorded flights to hard disk, place backup diskette in backup drive (if used) and select Restore Files from Utilities menu. Select appropriate options and click Restore. Software uncompressed selected backup file and copies it onto hard disk. The Restore from Archive function takes an archive and decompresses (restores) the files contained within. The Restore from Archive window is broken up into two areas: a FROM area and a TO area. Use the FROM area to choose a FROM directory and an archive file. Double click on directories to change directories. Single-click the archive to select it. Generally, archives are located in the C:\IMS\iMetOS\Archives directory. Use the TO area to navigate to a directory to place the flight files and reports. Notice that the path is given above the TO folders area. Click the Restore button to restore the files. Any files in the directory with the same name will be overwritten. To use the files immediately, restore them to the C:\IMS\iMetOS\Flights directory.



4.1.3 Delete Files The Delete Files (Delete Old Files) screen appears below:

Figure 4-4: Deleting Old Files

For irretrievable deletion of previously recorded flights from hard disk, select Delete Files from Utilities menu. Select file to be deleted and press Delete.

WARNING: Do not delete files which have not been backed up!

4.1.4 Enable Software Functions

Figure 4-5: Enable Software Function



The Enable Software Function allows the user to configure which items appear in the iMetOS menus. To enable a function in the menu, place a check mark by the function. To disable a function, uncheck the item. Close the window to accept any changes.

4.2 National Climatic Data Center The National Climatic Data Center Standard Non-real-time Transfer Format for Radiosonde Data (Revised 05/15/07).

4.2.1 Background This section 4.2 and sub-paragraphs describes the data format that the National Weather Service (NWS) and Cooperative Hurricane Upper Air System (CHUAS) use to deliver radiosonde observations to the National Climatic Data Center (NCDC). The CHUAS radiosonde ground system equipment formats each sounding, intended for relay to the NCDC, as three files, an identification file, a sounding data file, and a sounding high resolution data file. NWS field personnel copy data files from the upper air pc to another pc with internet access via diskette or file transfer cable and software, and transmit to NCDC via File Transfer Protocol (FTP) or e-mail attachment at the end of each month. The NCDC transcribes all incoming flight files to the NCDC upper-air quality control system to produce a digital archive.

4.2.1.1 NWS Identification File

The NWS Identification file has one 160 character record containing date and time of flight, station and equipment metadata, and surface weather parameters at the time of balloon release. The file naming convention for Identification files is “H” plus ascension number from the first of the year. RECORD POSITION ELEMENT NAME CODE DEFINITIONS AND REMARKS 1 STN-IND STATION NUMBER INDICATOR - This field

contains an indicator specifying the type of station number in the next field: 0 = WBAN NUMBER 1 = WMO NUMBER 2 = AIR FORCE AUGMENTED WMO NUMBER 3 = SHIP CALL SIGN 4 = MOBILE UNIT CALL SIGN

2-9 STN NUM STATION NUMBER - The number assigned to the station according to the numbering system specified in record position 1. Numbers should be right justified with leading blanks.

10-14 LAT LATITUDE - The station latitude in degrees and minutes. The last character is "N" or "S" as appropriate. When unknown, this field contains "9999N".

15-20 LONG LONGITUDE - The station longitude in degrees and minutes. The last character is "E" or "W" as appropriate. When unknown, this field contains "99999E".



21-24 ELEV ELEVATION - The height of the launch site in whole meters. Elevation should be right justified with leading blanks.

25-28 YEAR YEAR - The 4-digit year expressed at the hour of observation (UTC).

29-30 MONTH MONTH – The numeric (2-digit) month expressed at the hour of observation (UTC).

31-32 DAY DAY - The numeric (2-digit) day expressed at the hour of observation (UTC).

33-34 HOUR HOUR - The hour (24-hour clock) (2-digit) of observation (UTC). For synoptic hours (H=00, 06, 12, 18) the hour of observation will be H whenever the actual release time is H-60 to H+29. For example, the synoptic hour will be entered as 12 when the actual release is from 1100 to 1229 UTC. For regular synoptic observations the actual release should occur as close as possible to H-60. For non-synoptic hours, the hour of observation will be the nearest whole hour, H-30 to H+29 (e.g. the hour is entered as 10 when release is 0930 to 1029 UTC).

35-38 RELSE TIME TIME OF ACTUAL RELEASE – The hour and minute UTC (24-hour clock) (4-digit) of the actual release time.

39-42 ASCN NUM See Sections Below 39 RES FLD RESERVED FIELD – leave blank

40-42 ASCN NUM ASCENSION NUMBER - The ascension number for the year. The first release on or after Jan 1 will be numbered 001. Ascension numbers are right-justified with leading zeros.

43-46 OBSVR INIT OBSERVER INITIALS – The initials of the first and last name of the observer. Initials are right-justified with leading blanks.



47-49 DTA RDC SYS DATA REDUCTION SYSTEM – The type of data reduction system used at the site. 001 = MANUAL 002 = TIME-SHARE 003 = NOVA MINI COMPUTER 004 = MINI-ART 005 = MICRO-ART 007 = MARWIN, MRS 008 = MSS 009 = LAMS 010 = ASAP 011 = MV 7800 012 = AIR MET RESEARCH RAWIN SYSTEM 013 = VIZ W-9000 Meteorological Processing System 014 = RRS 018 = ATIR 019 = InterMet 1500

50-52 SONDE MAN SONDE MANUFACTURER – The manufacturer of the Sonde in use. 001 = VIZ 002 = VAISALA 003 = SPACEDATA 004 = AIR 005 = ATIR 006 = Sippican 007 = InterMet



53-55 SONDE TYP SONDE TYPE – The type of Sonde used at the station. 001 = VIZ J031 002 = VIZ ACCU-LOC 003 = VIZ A 004 = VIZ B 005 = VIZ MSS 006 = SPACEDATA-TRANSPONDER 007 = SPACEDATA-ARTSONDE 008 = SPACEDATA-MSS 009 = VAISALA RS80 (version unknown) 010 = VIZ B mod. 1492-520 (1680/403MHz)- TRANSPONDER 011 = AIR INTELLISONDE 012 = VIZ Mark II MICROSONDE 013 = VIZ C mod. 1492-530 (1680 MHz) Accu Lok 014-019 reserved 020 = VAISALA RS80-15N Navy MRS (OMEGA Navaid windfinding) 021 = VAISALA RS80-15P (OMEGA Navaid windfinding) 022 = VAISALA RS80-15L (Loran-C Navaid windfinding) ... 038 = VAISALA RS80-56 (Radio Direction Finding(RDF), 1680 MHz)- pressure cell 039 = VAISALA RS80-57 (RDF, 1680 MHz) 040-044 reserved 045 = Sippican HRFE 046 = Sippican LRFE ... 489 = VIZ B-2 (RDF, 1680 MHz) capacitance aneroid pressure sensor ... 500 = Sippican GPS 501 = InterMet GPS

56 SON/BAR IND SONDE/BAROSWITCH NUMBER INDICATOR – An indicator specifying the type of number in the next field. 0 = SONDE SERIAL NUMBER 1 = BAROSWITCH NUMBER

57-76 SON/BAR NUM SONDE/BAROSWITCH – The Sonde serial number or the Baroswitch number. The number is right justified in the field, with leading blanks. This “number” probably will include non-numeric characters



77-79 HUM TYP HUMIDITY TYPE – Type of humidity element used in the system 001 = Lithium Chloride Hygristor 002 = 1960's Carbon Hygristor 003 = 1980's Carbon Hygristor 004 = Humicap 005 = H-Humicap 006 = VIZ Mark II carbon hygristor 007 = Capacitance sensor 008 = Sippican Mark IIA Carbon Hygristor

80-82 TEMP TYP TEMPERATURE TYPE – Type of temperature element used in the system. 001 = Rod Thermistor 002 = Bead Thermistor 003 = Chip Thermistor 004 = Capacitive Bead

83-85 PRESS TYP PRESSURE TYPE – Type of pressure element used in the system. 001 = Baroswitch 002 = Transducer - oven controlled 003 = Transducer - non-oven controlled 004 = Derived (Transponder) 005 = Capacitive Aneroid 006 = Resistive strain gauge 007 = Derived GPS

86-88 TRK TYP TRACKING TYPE – The type of tracking system. 001 = 72-2 002 = SCR-658 003 = WBRT-57 004 = WBRT-60 005 = GMD-1 006 = GMD-1A 007 = GMD-1B 008 = GMD-5 009 = OMEGA 010 = LORAN 011 = ART-1 012 = ART-1R 013 = ART-2 014 = ART-2R 015 = MDS 016 = MSS RANGING 017 = RADIO THEODOLITE (InterMet-1500) 018 = Global Positioning System (GPS)



89 TRNSP TRANSPONDER – is a transponder used. 0 = No 1 = Yes

90-92 BAL MAN BALLOON MANUFACTURER – The manufacturer of the balloon. 001 = KAYSAM 002 = WEATHERTRONICS 003 = KKS 004 = Totex 999 = Other

93-96 BAL WGT/TYP BALLOON WEIGHT/TYPE – Nominal weight of the balloon in grams (weight is right justified with leading blank) or balloon type as follows: 0001 = GP26 0002 = GP28 0003 = GP30 0004 = HM26 0005 = HM28 0006 = HM30 0007 = SV16 9999 = Other

97-98 BAL AGE BALLOON AGE – Age of the balloon in months. Age is right justified with leading blank.

99 TRN REG TRAIN REGULATOR – Was a train regulator used? N = No Y = Yes

100 PBL LGT PIBAL LIGHT – Was a PIBAL Light used? N = No Y = Yes

101 PBL TYP PIBAL TYPE – PIBAL wind equipment type according to WMO Code Table 0265. 0 = Pressure instrument associated with wind-measuring equipment 1 = Optical Theodolite 2 = Radio Theodolite 3 = Radar 8 = Satellite Navigation (or GPS)



102-103 REASON TERM REASON FOR TERMINATION – Reason for termination of the flight. 01 = Balloon burst 02 = Balloon forced down by icing 03 = Leaking or floating balloon 04 = Weak or fading signal 05 = Battery failure 06 = Ground equipment failure 07 = Signal interference 08 = Radiosonde failure 09 = Excessive missing data 10 = Other

104 NUM RCP RECOMPUTES – The number of times this flight has been recomputed. Flight not recomputed is “0”.



105-113 CLOUDS-WX CLOUDS AND WEATHER - The observation of the clouds and weather at the time of release. The field is of the form NhCLhCMCHWWWW, where:

Nh = The amount of low or mid-level clouds

present according to WMO Code Table 2700. 0 = 0 okta (tenths) 1 = 1 okta (1/10) or less, but not zero 2 = 2 oktas (2/10-3/10) 3 = 3 oktas (4/10) 4 = 4 oktas (5/10) 5 = 5 oktas (6/10) 6 = 6 oktas (7/10-8/10) 7 = 7 oktas (9/10) or more, but not overcast 8 = 8 oktas (10/10) 9 = Sky is obscured by fog and/or other meteorological phenomena - = Cloud cover is indiscernible for reason other than "9" or observation not made. The WMO code figure "/" must be converted to "-". CL,CM,CH = The cloud type according to WMO

Code Tables 0509, 0513, and 0515. Code figure "/" must be converted to "-". h = WMO Code Table 1600 for the height above ground of the base of the lowest cloud seen. Code figure "/" must be converted to "-". WW = Present weather according to WMO Code Table 4677. Up to two types of present weather or obscurations may be entered. If present weather is not observed, enter "////" in this field (WWWW).

114-116 SFCWND DIR SURFACE WIND DIRECTION – The direction of the surface wind at time of release in whole degrees. Wind Direction is right justified with leading zeros.

117-119 SFCWND SPD SURFACE WIND SPEED – The speed of the surface wind at time of release in meters per second to the nearest 0.1 meter per second. Do not enter the decimal point; 12.3 meters per second = 123 Wind Speed is right justified with leading blanks



120-122 WIND AVE INT WIND AVERAGING INTERVAL – The interval of time or height over which the wind is derived. 000 = None (instantaneous) 001 = Two minutes to 14km (MSL), four minutes above 14km (MSL). (Pre-1990 FMH Standard, NWS) 002 = Post-1989 FMH Standard 003 = 20 seconds to 15K ft., 60 seconds above 15K ft. 004 = 30 seconds up to 2500m AGL, 45 seconds up to 5000m AGL, 60 seconds up to 7500m AGL, 75 seconds up to 10 km AGL, 90 seconds up to 15 km AGL, 105 seconds up to 20 km AGL, 120 seconds above 20 km AGL. 005 = Four minutes. for the entire flight 006 = Two minutes. for the entire flight 007 = Variable 008 = One Minute smoothing

123-134 See Sections Below

CPRTYP TYPE OF CORRECTION – The type of correction applied to individual data elements by automated systems or observer.

123-124 CORTYP-P PRESSURE CORRRECTIONS 00 = No correction applied 01 = NASA temperature correction 02 = EMCWF temperature correction ... ... 88 = Unknown

125-126 CORTYP-Z HEIGHT CORRECTIONS 00 = No correction applied 01 = Local gravity correction 02 = Standard gravity correction ... ... 88 = Unknown



127-128 CORTYP-T TEMPERATURE CORRECTION 00 = No correction applied 01 = NASA radiation correction 02 = EMCWF radiation correction 03 = NMC radiation correction 04 = Vaisala RSN-93 solar and infrared radiation correction ... ... 11 = NASA lag correction 12 = EMCWF lag correction 13 = NMC lag correction ... ... 21 = NASA radiation and lag correction 22 = EMCWF radiation and lag correction 23 = NMC radiation and lag correction ... ... 88 = Unknown 89 = Sippican W-9000 Solar Correction 90 = Sippican Solar and Infrared 91 = InterMet Solar and Infrared

129-130 CCORTYP-H HUMIDITY CORRECTIONS 00 = No corrections applied 01 = NASA lag correction 02 = EMCWF lag correction 03 = NMC lag correction ... ... 88 = Unknown

131-132 CORTYP-TD DEW POINT CORRECTIONS 00 = No corrections applied 01 = NASA lag correction 02 = EMCWF lag correction 03 = NMC lag correction ... ... 88 = Unknown



133-134 CORTYP-W WIND CORRECTIONS 00 = No corrections applied 01 = Elevation angle correction 02 = Ranging correction ... ... 88 = Unknown NOTE: At this writing, the types of corrections which may be applied to the data have not been determined. Input from various agencies will be used to develop initial codes and correction types.

135-144 SOFT VER SOFTWARE VERSION – The version of software in use with the specified recording system. Enter the software version left-justified with trailing blanks

145-160 RES FLD RESERVED FIELD – Leave blank

4.2.1.2 NWS Data Record

The NWS Data File contains a variable number of 80 character records, each containing data for one reported level. Data records contain flight ascension number, elapse time since release, layer type, observed elements, and data quality indicators. The file naming convention for Data files is “T” plus ascension number from the first of the year. RECORD POSITION ELEMENT NAME CODE DEFINITIONS AND REMARKS 1-4 ASCN NUM See sections below

1 RES FLD Leave blank 2-4 ASCN NUM ASCENSION NUMBER - The ascension number

for the year. The first release on or after Jan 1 will be numbered 001. Ascension numbers are right-justified with leading zeros.

5-9 ELPSD TIME ELAPSED TIME - The time in minutes and seconds (mmmss) (5-digits) since the actual release time.

10-15 PRESS PRESSURE - Atmospheric pressure at the current level in hundredths of hectopascals (0.01 millibars). Pressure is right justified with leading blanks

16-20 HGT HEIGHT - Geopotential height of the pressure level in whole geopotential meters. (MSL). Height is right justified with leading blanks.

21-24 TEMP TEMPERATURE - Dry-bulb temperature to the nearest 0.1 degree Celsius. Temperature is right justified with leading blanks.



25-28 REL HUM RELATIVE HUMIDITY - The relative humidity to the nearest 0.1 percent. Relative Humidity is right justified with leading blanks.

29-31 DPDP DEW POINT DEPRESSION - The dew-point depression to the nearest 0.1 degree Celsius. Dew Point is right justified with leading blanks.

32-34 WND DIR WIND DIRECTION - The wind direction to the nearest whole degree. Wind Direction is right justified with leading blanks.

35-38 WND SPD WIND SPEED - Wind speed to the nearest 0.1 meter per second. Wind Speed is right justified with leading blanks.



39-40 TYP LEVEL TYPE OF LEVEL – The reason for selection of the level. 00 = High resolution data sample 01 = Within 20 hectopascals (mb) of the surface 02 = Pressure less than 10 hectopascals (mb) 03 = Base pressure level for stability index 04 = Begin doubtful temperature, altitude data 05 = Begin missing data (all elements) 06 = Begin missing relative humidity data 07 = Begin missing temperature data 08 = Highest level reached before balloon descent because of icing or turbulence. 09 = End doubtful temperature, altitude data 10 = End missing data (all elements) 11 = End missing relative humidity data 12 = End missing temperature data 13 = Zero degree crossing for the RADAT 14 = Mandatory pressure level 15 = Operator added level 16 = Operator deleted level 17 = Balloon re-ascended beyond previous highest level 18 = Significant relative humidity level 19 = Relative humidity level selection terminated 20 = Surface level 21 = Significant temperature level 22 = Mandatory temperature level 23 = Flight termination level 24 = Tropopause 25 = Aircraft report 26 = Interpolated (generated) level 27 = Mandatory wind level 28 = Significant wind level 29 = Maximum wind level 30 = Incremental wind level (e.g., 1-minute, fixed regional) 31 = Incremental height level (generated 32 = Wind termination level 33 = Pressure 100 to 110 hectopascals, when no other reason applies. 40 = Significant thermodynamoic level (reason for selection unknown) 41 = Significant relative humidity level, using NCDC criteria. 42 = Significant temperature level, using NCDC criteria. 43 = Begin missing wind data. 44 = End missing wind data.



41-43 SQP SIGNAL QUALITY – Signal quality for the element (Pressure) expressed as a percentage of individual samples accepted

44-46 SQT SIGNAL QUALITY – Signal quality for the element (Temperature)

47-49 SQU SIGNAL QUALITY – Signal quality for the element (Humidity)

50-52 SQD SIGNAL QUALITY – Signal quality for the element (Dew-Point Temperature)

53-54 WQET ELEMENT QUALITY FLAGS - These fields contain the results (Elapsed Time) of any quality control procedures for identifying suspect and doubtful individual elements:

55-56 EQP (Pressure/Ranging) 00 = Element is correct 01 = Element is suspect

57-58 EQH (Height) 02 = Element is doubtful 03 = Element Failed QC checks 04 = Replacement value (correction)

59-60 EQT (Temperature) 05 = Estimated value 06 = Observer edited value 09 = Element not checked

61-62 EQU (Humidity 63-64 EQD (Dew-point depression) 65-66 EQWD (Wind direction) 67-68 EQWS (Wind speed) 69-80 RES FLD RESERVED FIELD Leave Blank The data records are repeated as many times as necessary to record all levels of the flight. All fields must be right-justified (least significant digit in the rightmost position) unless specified otherwise. All missing fields must be a 9 filled unless specified otherwise. Do not enter decimal points. The decimal point is implied by the field position.

4.2.1.3 NWS High Resolution Data

The NWS High Resolution Data File contains a variable number of the first 38 character records listed in the Data File (above table), each containing data for 2 second intervals. Data records contain flight ascension number, elapse time since release and observed elements. The file naming convention for High Resolution files is “R” plus ascension number from the first of the year.



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Revision B June 2009 5-1 System Setup

CHAPTER 5 SMC SYSTEM SETUP

5.1 System Setup The System Setup menu is accessed from the Flight Screen

Figure 5-1: System Setup

From the System Setup menu, enter the following (refer to section 5.1.1 through 5.1.12 below):


System Setup 5-2 June 2009 Revision B

5.1.1 Communication Ports Parameters

Figure 5-2: Comm Ports Parameter

This setting affects the MetServer application, which handles all communications between the CPU and the peripherals such as the 403 Receiver. Configuring the Comm Ports Parameter as a “Local Server” disables the IP address selection. The MetServer communicates with the external devices on the Computer Workstation. When the MetServer is not configured as a local server, the IP address selection is enabled. Type in a valid IP address of a computer that is running the iMetOS as a local server. The MetServer application enables TCP/IP communication with the host computer running the iMetOS. The client can then interface with the host’s peripherals as if they were its own.

5.1.2 Display Color Parameters

Figure 5-3: Color Parameters



It is recommended to accept the default color selections set at the factory, by clicking OK. To change any graph color, click on the desired parameter, then press Select under the respective graph list. A pane will appear showing the available colors. Click on the desired color and press OK. The new color will appear instead of the old color next to the desired parameter. Press OK to accept or Cancel to reject.

5.1.3 System Parameters I

Figure 5-4: System Parameters 1

Set only the following parameters (do not change defaults set at the factory for other parameters). Click OK when all of the following parameters have been set.

− Use Password: Check only if password use is desired.



NOTE: If password use is selected, entrance to system will be denied the next time software is accessed unless password is correctly entered.)

– Password for Enter: requires a user password for setup windows.

– Password for Exit: requires the operator to enter a password to exit the iMetOS, to help prevent accidental closure during a flight.

– Display Lat/Long in DMS: check to display latitude and longitude in degrees, minutes, and seconds

– Terminate Flight Automatically: set to end logging automatically after an event signaling the end of a flight, such as a balloon burst.

– Extrapolate Last Wind Level: set to extrapolate the final wind level at the flight apex.

– Temperature Correction: set to use a solar correction.

– Temperature in °C (K): set to display temperatures in degrees Celsius (uncheck to display in Kelvin).

– Height in Meters: set to display height in meters (uncheck to display in feet)

– Load Standard Atmosphere: draws standard atmosphere lines on graphs.

NOTE: Do not change the following parameters. These are set at the factory for optimal

performance.

– Main Meridian: enter only if UTM network use has been selected.

– Wind Time Factor: an integration time factor for wind computation.

– Flight Seconds: the maximum possible length of flight in seconds. This sets aside memory for storing data. If the time is too short, data may be unreliable.

– Log File Time Interval: the time interval for logging data record, in seconds.

– Flight Files Directory: the directory where all reports and flight data will be logged.

– Missing data time: internal valued used in data interpolation and error checking.

NOTE: InterMet highly recommends that the default value not be changed. Changing this value will result in changes in smoothed data. This value is optimized for this system.

– Balloon burst identification time: used by the iMetOS to indicate how far back in time to

determine an actual balloon burst occurred. The default value has been optimized for this system.



5.1.4 System Parameters II

Figure 5-5: System Parameters 2

To make any changes, either type in a new numerical value or select a new item from the pulldown menus. Click OK to accept any changes or Cancel to reject any changes. – Window Size:

– Left: the initial position of the iMetOS from the left side of the screen, in pixels

– Top: the initial position of the iMetOS from the top of the screen, in pixels

– Width: the width, in pixels, of the iMetOS

– Height: the height, in pixels, of the iMetOS – Default Output Device: set the default output device for reports

– Printer: automatically prints the reports upon generation

– Screen: creates a report on disk and displays the reports on screen

– File: creates a report on disk in the Flights directory

– Comm Port: automatically sends the reports out over a COM port

– Drive A: creates a report on disk on the A: drive

– Drive B: creates a report on disk on the B: drive

– Send Host Protocol: the protocol used for sending a report out over a COM port



5.1.5 NWS Parameters

Figure 5-6: NWS Parameters

Set following parameters. Click OK when all of the following parameters have been set.

− Station Number Indicator (WBAN Number, WMO Number, Air Force Augmented WMO Number, Ship Call Sign, Mobile Unit Call Sign)

− Observers Initials

− Balloon Manufacturer (Kaysam, WeatherTronics, Totex)

− Balloon Weight

− Balloon Age

− Train Regulator (No, Yes)

− Reason for Termination (Balloon Burst, Balloon Forced Down by Icing, Floating Balloon, Weak Signal, Battery Failure, Ground Equipment Failure, Signal Interference, Radiosonde failure, Excessive Missing Data, Others)

− Number of times this flight Recomputed

− Pibal Light (No, Yes) Note: Items above (Figure 5-6) should be changed before archiving or exiting flight to

correct values or reasons under pull down menus. All this information is useful when analyzing the flight data.



5.1.6 WMO Reports Selection

Figure 5-7: WMO Reports Selection

NOTE: Screen of actual system may show more or fewer report options. Enter as required

and click OK. The above WMO Reports Selection will cover all situations and it is highly encouraged that all sites select the above options.

The WMO Reports Selections menu should be as indicated in Figure 5-7. The iMetOS only archives the products that have been generated. The windows checked as shown in figure 5-7 will ensure that the necessary products have been generated and to cover all situations (like early termination) and other unforeseen operations. The WMO Reports Selection Menu above show the removal of the File Extension for the three NWS files. The iMetOS automatically archives the NWS files without the File Extension after this procedure has been saved.



5.1.7 WMO Coding Parameters I

Figure 5-8: WMO Coding Parameters 1

Enter as required and click OK – Number of Groups Per Line (leave as 10)

– Number of Blank Lines Between Messages ( Blanked Out)

– Maximum Number of Tropopauses (leave as 3)

– Lowest Tropopauses Pressure (leave as 80.0)

– WMO Sounding System Used ( blanked out)

– Humidity Cutoff Temperature (Should be -99.9)



5.1.8 WMO Coding Parameters II

Figure 5-9: WMO Coding Parameters 2

Enter as required and click OK. The detailed WMO Abbreviated Heading is in paragraph 2.25.1.

5.1.9 MetServer Configuration The MetServer configuration file is used to configure the MetServer application. It is located in the C:\IMS\iMetOS\MetServer directory. The file is set by default at the factory and should not be changed.


Revision B June 2009 6-1 CDU Operating Procedures

CHAPTER 6 CDU OPERATING PROCEDURES

6.1 General The antenna continuously tracks a radiosonde from launch until termination of the flight as the radiosonde is carried up through the atmosphere by an aerological sounding balloon. The antenna is designed to be operated by a Control Display Unit (CDU) located with the antenna, or by commands from the System Computer located in the weather office. At the operational sites, the Antenna is operated by observers who are responsible for preparing the radiosonde for flight and releasing it to be carried up through the atmosphere. Operating procedures contained in this chapter cover commands by the CDU.

6.2 Control Display Unit (CDU) Each CDU is housed in a light-weight rectangular metal casing. The width of the casing is such that it is easily held in one hand. An LCD display is mounted in the upper section of the face of the casing. Each CDU incorporates a keypad on the lower section of the face of the casing for numeric and functional operations plus a set of direction controls for slew/level control. Each CDU has an interface cable which is connected between the base of the CDU and the SCA.

The display is a 120 x 64 pixel graphics LCD display module. The LCD includes backlighting, and has an extended temperature operating range. The backlighting is permanently enabled.

The keypad consists of 15 keys, arranged in a 3x5 matrix and 4 direction control keys, as shown in a graphic representation in Figure 6-1. The keys are made of molded silicon. They have a full tactile feel and a travel of 1 to 2 mm. A short, fixed-volume beep accompanies each key press (or key repeat).

Ant Rec Sys

1AFC On 2AFC Off 3

4Track On 5Track Off 6

7 8 9

Back 0 Fast ENTER

+

-

Figure 6-1: CDU Keyboard


CDU Operating Procedures 6-2 June 2009 Revision B

6.2.1 User Interface Control of the station and CDU is achieved via an interface that implements quick, logical steps to guide the user to the desired result. Often used functions are available with a minimum of keystrokes and screen changes. Feedback to any user input is apparent, positive and effectively instantaneous.

Space constraints on the keyboard dictate functions to be accessible by a menu selection system. Often-used functions are implemented to require a minimum number of keystrokes before they are executed.

There is a main or default display mode called the Idle State and three functional menu driven modes relating to the Antenna or “Ant” functions, the Receiver or “Rec” functions and the System or “Sys” functions. Intermediate or error screens indicate time delays or response failures from the system.

6.2.1.1 Idle State Overview

The Idle State is the most used mode and functions available from it require the fewest keystrokes.

6.2.1.1.1 Idle State

Under normal conditions, the CDU is in the Idle State. In this state, the screen gives an upper level set of data on the station operation. It is displayed and updated at a suitable rate such that the observer has fresh, flicker-less data required for the situation.

The data screen that is displayed in this state may also be selected via the SYS key and the Data sub-menu.

After initialization, the CDU begins operation in the idle state. Some data entry requires selection of menus; perhaps submenus, and entry of numeric data to complete an operator instituted action. If the operator has stopped pressing keys for approximately 60 seconds before finishing the keystroke action, the non-completed keystrokes or operations are cancelled and the CDU reverts to the Idle State.

6.2.1.1.2 Menus

Numeric-selection menus are used to guide the user in their choice at any particular state. Selection of an item is achieved by pressing the appropriate numeric key.

The Back key is used to revert to the menu level or state prior to the one currently displayed.

6.2.1.1.3 Keyboard

Some of the numeric keys are used for quick access to often-used functions. These functions are available when the CDU is not expecting a numeric input. The functions are AFC On/Off and Tracking On/Off.

The numeric keys are used to select numbered menu items, or to enter numeric data. A fixed decimal place position is indicated in entry fields for floating-point numbers.

The Back key is used to delete individual numbers entered in a numeric entry screen. If a menu is displayed, this key is used to revert to the menu level state above the one currently displayed.

The 3 menu keys along the top row, if pressed, cause the CDU and station to abort the current operation, menu or state and display the applicable top-level menu for the particular menu key pressed.



6.2.1.1.4 Direction Controls

The direction control keys, in combination with the “0/fast” key, slew the antenna when the CDU is in the Idle State. The speed of slewing is dependent on the length of time the key(s) are held down. Table 6-1 details the operation of the direction control keys.

Table 6-1: Direction Controls

Initial Slewing Speed Action Final Slewing Speed Antenna stationary Direction control pressed without “0/fast” 1°/second Antenna stationary Direction control pressed with “0/fast” 10°/second 1°/second Direction control held for > 4 seconds 5°/second 1°/second “0/fast” key pressed 10°/second 5°/second “0/fast” key pressed 20°/second 5°/second Direction control released and repressed 1°/second 10°/second Direction control held for > 4 seconds 20°/second 10°/second “0/fast” key released 1°/second 20°/second Direction control released and repressed 10°/second 20°/second “0/fast” key released 5°/second Elevation and azimuth slewing movements may be obtained simultaneously by pressing both vertical and horizontal direction keys.

Should the station be operating in auto-tracking mode when a direction control key is pressed, the station is taken out of the auto-tracking mode and set to manual mode if that key is pressed for at least ½ second.

Antenna slewing via the direction keys is not active in non-Idle State screens.

The Up (+) and Down (-) direction control keys are also used in the following situations:

− Manual tuning, where the four available tuning speeds, using the analogy of tuning speed versus angular rotation speed detailed above Error are 10kHz, 100kHz, 500kHz and 1MHz per second.

− Volume level, under the SYS menu

− LCD contrast adjustment is under the SYS menu

− To add a “+’ or ‘-‘ to the front of signed numeric data entries.

6.2.1.2 Antenna Menu Key

Pressing “ANT” key causes the CDU to display a menu of operations related to the control and positioning of the antenna. Options 2, 3 and 4 are not displayed when the station is operating in the Auto Tracking Mode.

ANTENNA CONTROL 1:Position 4:Auto / 2:To Zero 5:Manual 3:Search 6:Calib



6.2.1.2.1 Antenna Positioning

When option 1 is pressed, the CDU displays a level 2 menu screen. In this condition, the user is asked whether the desired movement is to be to an absolute position, or if a relative movement is desired.

ANTENNA POSITIONING 1:Absolute 2:Relative

Selection of option 1 causes the CDU to display the following screen:

ABSOLUTE POSITIONING 1:Azimuth 2:Elevation

Selection of option 1 or 2 causes the CDU to display a numerical data entry screen. The screen for option 1 is shown below:

ABSOLUTE POSITIONING Azimuth +000.00°

Numerical entry is now permitted. Numbers are entered at the right hand position, and scroll towards the left. The sign of the entry can be altered using the direction control keys (Up = '+', Down = '-'). The Back key deletes the last number entered, and scrolls all other numbers one position to the right. Pressing Back key when the display shows 000.00 returns the CDU to the previous screen. The ENTER key terminates the operation. On pressing ENTER, the station implements the desired movement in the selected axis, and the CDU returns to the Idle State.

Range checking is initiated checking for Azimuth entries outside -360.00 to +360.00 and Elevation entries outside - 5.00 to +91.50. Entries outside of these ranges produce an audible and visual warning. The user may then modify the value.

ABSOLUTE POSITIONING Elevation -012.49° ERROR:Illegal value!

If option 2 (Relative Positioning) is selected in the level 2 menu screen above, the CDU displays the following level 2 menu screen:



RELATIVE POSITIONING 1:Azimuth 2:Elevation

Selection of option 1 or 2 causes the CDU to display a numerical data entry screen. The Operation will proceed as detailed above.

The maximum relative movement in the Azimuth axis is ±180.00°. The maximum relative movement in the Elevation axis is ±96.50°.

6.2.1.2.2 Zero Position

When option 2 is pressed, the CDU displays the following level 2 menu screen:

RELATIVE POSITIONING 1:Azimuth 2:Elevation 3:Both Axis

Selection of an option causes the station to slew the selected antenna axis or axes to the 0.00° position and the CDU returns to the Idle State.

6.2.1.2.3 Antenna (Limited) Search

When option 3 is pressed, the CDU starts with requests for further data entry before a limited search is begun. Limited search moves the Antenna in azimuth and elevation over a limited range of angles attempting to find the direction to point to maximize the signal received from the radiosonde. A numerical data entry screen is displayed for entry of the expected signal strength of the radiosonde when it is located. The value entered here is stored for recall as the initial value for this entry the next time that a search is requested.

ANTENNA SEARCH Find a signal above

-065DBm

The next screen is used to enter the cone angle of the search. This is the maximum angle that is to be described by the limited search. The value entered here is stored for recall as the initial value for this entry the next time that a search is requested.

ANTENNA SEARCH Maximum cone angle

10°

After entry of the maximum cone angle, the CDU instructs the station to commence a limited search, centered on the current elevation and azimuth angles with signal strength and cone search angles as selected. The CDU then revert to the Idle State, displaying the General Data screen.



6.2.1.2.4 Auto Tracking

When option 4 is pressed, the station enters the Auto Tracking Mode. In the Auto Tracking Mode, the system controls the antenna movement and positioning to maintain it aligned with the radiosonde. A tick is displayed alongside this menu option if the station is already in the Auto Tracking Mode.

The CDU reverts to the Idle State after selecting this option.

6.2.1.2.5 Manual Tracking

When option 5 is pressed, the station enters the Manual Tracking Mode. In this mode, the antenna remains stationary unless moved by a command received from a CDU or the workstation. A tick is displayed alongside this menu option if the station is already in the Manual Tracking Mode.


6.2.1.2.6 Calibration

When option 6 is pressed, the CDU progresses through a number of screens, sending instructions to the station, telling the user steps to take, and being taken for tracking calibration of the station. The first screen shown is as follows:

After the user presses ENTER, the CDU sends instructions to the station to perform the following operations:

− Move the antenna to point to the pre-configured location of the test signal

− Tune to the test signal

− Enable receiver AFC

− Enable auto-tracking

− Sample antenna angular data for approximately 25 seconds

− Evaluate tracking performance by determining average antenna angles and standard deviations

− Store electrical boresight offsets if the results are judged to be acceptable.

The CDU displays a bar graph showing the progress of the calibration operation. The entire operation aborts with an appropriate message should any problems be encountered.

The CDU reverts to the Idle State after completion of the calibration.

TRACKING CALIBRATION Please prepare the test signal source ENTER to proceed



6.2.1.3 Receiver Menu Key

Pressing the “REC” key causes the CDU to display a menu of operations related to the control of the receiver as follows:

RECEIVER CONTROL 1:Auto / 4:Tune 2:Manual 5:Goto Frq 3:Search

6.2.1.3.1 Automatic Frequency Control (AFC) On

When option 1 is pressed, the station receiver enters the Automatic Frequency Control Mode. With AFC on, the receiver controls its frequency to track that of the radiosonde. A tick is displayed alongside this menu option if the receiver is already exercising AFC.


6.2.1.3.2 Manual Frequency Control Off

When option 2 is pressed, the station receiver enters the Manual Frequency Control Mode (no AFC). With AFC off, the receiver frequency is not varied, except following appropriate instructions from the CDU or workstation. A tick is displayed alongside this menu option if the receiver is in Manual Frequency Control mode.


6.2.1.3.3 Receiver Search (Automatic Signal Location)

Selecting option 3 causes the CDU to display a series of numerical data entry screens, after which search for the frequency of the radiosonde is launched.

The first screen permits entry of the starting (lower) frequency of the search. The value entered here is stored for recall as the initial value for this entry screen the next time that a frequency search is requested.

RECEIVER SEARCH Lower Frequency 1668.40MHz

Numeric entry is as detailed above. Range checking is implemented when ENTER is pressed. (The CDU shows a brief error message and aborts the operation if an illegal value is entered.)

The second screen permits entry of the ending (upper) frequency of the frequency search. As above, the value entered here is stored for recall as the initial value for this entry screen the next time that a search is requested.

RECEIVER SEARCH Upper Frequency 1700.00MHz



After entry of the Upper Frequency, the CDU displays the search screen, the receiver AFC is turned off, and the receiver is instructed to begin the frequency search operation. The screen indicates the current frequency and signal strength numerically and graphically.

Freq:1684.23MHz Srch F:█████████████ SIG:-75DBm S:███████

Pressing the ENTER or Back keys during a search ends the search and causes the receiver to hold the last frequency. If ENTER is pressed, the CDU reverts to the Idle State. If Back is pressed, the CDU reverts to the previous screen.

ENTER should be pressed if/when a suitable signal has been located to restore the CDU to the Idle State.

6.2.1.3.4 Tune (Manual Tuning)

Pressing option 4 takes the CDU to the Manual Tuning screen. The user may now manually change the receiver frequency, using the Up and Down direction control keys. Tuning is carried out in steps of 10 kHz, 100k Hz, and 500 kHz or 1MHz.

The receiver AFC may be turned off or on using the “1/AFC Off” and “2/AFC On” keys.

Freq:1684.23MHz Man F:████████ SIG:-98DBm AFC OffS:███

Pressing ENTER takes the CDU back to the Idle State. Pressing Del/Back takes the CDU back to the previous screen.

6.2.1.3.5 Goto Frequency

Selecting option 5 causes the CDU to display a numerical data entry screen, which permits entry of the frequency to which it is desired to tune the receiver.

RECEIVER TUNING Go To Frequency 1680.00 MHz

Numeric entry is as detailed above. Range checking is implemented over the range 1668.40MHz to 1700.00MHz. When ENTER is pressed, AFC is turned off (if it was on), the receiver frequency is changed and the CDU reverts to the Idle State.

6.2.1.4 System Menu Key

Pressing of the “SYS” key causes the CDU to display a menu of options to specify the operation and configuration of the CDU.



CDU CONTROL MENU 1:Data 4:Volume 2:LCD 5:Master /3:Audio 6:Version

Note that the Master option has a “tick” next to it (as shown) if it is currently enabled.

6.2.1.4.1 Data

When option 1 is pressed, the CDU displays a level 2 menu screen as follows:

DATA DISPLAY 1:General 2:Status 3:Position

General Display:

When option 1 is pressed, the CDU reverts to the Idle State, and displays the General data screen. The General data screen reports antenna angles, tracking errors, receiver frequency, signal strength, and antenna and receiver status indicators (e.g., Man, Track, Search, AFC, Scan, Squelch) as follows:

Az:284.57° Err:026>El:007.29° Err:018^F :1678.34 SIG:-102 Ant:Man Rx :AFC

Status Display:

When option 2 is pressed, the CDU reverts to the Idle State, and display the Status data screen whenever it is in this state. The Status data screen reports LRU POST Status, SCA Input voltage and current as follows:

SYSTEM STATUS Faults : None VOLTAGE : 23.6V Current : 4.7A

Position Display:

When option 3 is pressed, the CDU reverts to the Idle State, and display the Position data screen whenever it is in this state.

STATION LOCATION Lat : 032°18'37.8''S Long: 018°44'07.2''EALT : 356M

6.2.1.4.2 LCD Contrast

When option 2 is pressed, the CDU displays a screen that the user uses to adjust the contrast of the LCD display as follows:



LCD CONTRAST ADJUST C:█████████ +: Increase -: DECREASE

Pressing ENTER takes the CDU back to the Idle State.

6.2.1.4.3 Audio Outputs

When option 3 is pressed, the CDU displays a level 2 menu screen. From this menu the user selects which audio channel will be output.

AUDIO OUTPUTS 1:Tuning Aid 2:FM /

Note that the CDU either outputs a “Tuning Aid” or the received FM signal. The currently selected output will have a ‘tick’ next to it

6.2.1.4.4 Volume Level

When option 4 is pressed, the CDU displays a screen which the user uses to adjust the volume of the audio output as follows:

VOLUME CONTROL V:███████ + : Increase - : DECREASE

A continuous sample tone is generated during this operation.


6.2.1.4.5 Master Control

(This option is only be displayed and available for selection if the CDU is being used as the Local CDU.)

When option 5 is pressed, the station toggles Local CDU Master Control on or off. The CDU reverts to the Idle State after selecting this option.

When the station is in Master Control mode, only the Local CDU may control antenna movements.

6.2.1.4.6 Version Information

When option 6 is pressed (option 5 if Master Control is not available) the CDU displays the manufacturer, the CDU location (type), the firmware version information, and a copyright notice.



INTERMET SYSTEMS LAUNCH AREA CDU V3.21 ©2002


6.2.1.5 Intermediate and Error Screens

Should a requested operation require a command to be sent to the tracking station, the CDU will display the following screen:

Waiting for response From system...

Should the system not respond as expected, error screens are displayed. If no response is obtained, the following screen is displayed:

*** ERROR *** System does not Respond!

If a requested operation resulted in an error response, it is displayed as follows:

*** ERROR *** Error #xx Descriptive Message

The error message text will be one of those shown in Table 6-2.



Table 6-2: CDU Error Messages

Error Number Descriptive Message Reason 00 Bad Checksum Unlikely to occur. May be a result of noise. 01 Bad Numerical Value Unlikely to occur. May be a result of noise. 02 AFC On Attempt to manually tune receiver while AFC is

enabled. 03 Auto Tracking On Attempt to move Antenna while automatic

tracking is enabled. 04 Destination Unknown Unlikely to occur. May be a result of noise. 05 Invalid Operation Attempt to change to an unobtainable Antenna

position or receiver frequency (e.g., in relative movements).

06 Operation Locked Out Local CDU has locked out this operation. 07 Internal Comms Error Unlikely to occur except if internal LRUs are

faulty. 08 BIT In Progress System busy with off-line tests. Operation is

unavailable at this time. 09 Unknown command Unlikely to occur. May be a result of noise. 10 Command Format Unlikely to occur. May be a result of noise. 12 Busy Initializing System is busy with initialization. 13 Busy Warming Up System is busy with warm up operations. 14 Busy Calibrating System is busy with tracking offset calibration. 60 Busy Moving Antenna movement is currently in progress.

Re-attempt the command once movement has ceased.

61 Motor Fault Control of this motor is not available. Refer to POST results.

62 Motor overcurrent Motor is experiencing an over-current. Investigate and rectify the situation.

63 Search in Progress Antenna movement is not permitted while a search is in progress


Revision B June 2009 7-1 Quality Control of Data

CHAPTER 7 QUALITY CONTROL OF DATA

7.1 Introduction Although upper-air observers are required to quality control their soundings prior to dissemination, not all data errors or problems can be identified, corrected, or deleted. Effective data quality control is a multi tiered process involving the upper-air observer, NCEP, NCDC, and administrative offices. This chapter provides an overview of how upper-air soundings are quality controlled.

7.2 Observer Quality Control of Upper-air Soundings Observers must make every effort to quality control their rawinsonde observations prior to dissemination to data users. Transmitting poor quality soundings can lessen the accuracy of weather forecasts and warnings. Here are guidelines for ensuring high quality upper air observations: 1. Inflate the balloon correctly. Observers must strive for an average balloon ascension rate

between 275 and 350 meters/minute from surface to flight termination for each sounding. Stations should have no more than 5% of their flights per month with ascent rates below 275 meters/minute or above 350 meters/minute. Average ascension rates below 275 meters/minute reduce ventilation of the temperature and RH sensors and can cause loss of valuable data. Ascension rates above 350 meters/minute increase gas costs per flight and typically result in lower burst heights.

2. Prepare the radiosonde in accordance with the instructions. To ensure the radiosonde functions correctly the instrument preparation instructions must be followed exactly as stated. The radiosonde sensor boom or other components must not be manipulated in a manner not in accordance with the radiosonde preparation instructions. With good intent, some observers bend the sensor boom differently from that noted in the instructions and believe it will provide better data or do no harm. In most cases these changes don't work and cause very erroneous data. Following all the radiosonde preparation instructions will help ensure a problem free sounding.

3. Do not use flight trains less than 25 meters in length. When the balloon is exposed to sunshine, its skin becomes significantly warmer than the surrounding air. When a short flight train is used heat from the balloon reaches the temperature sensor, contaminating the measurements.

4. Do not excessively smooth out bad data in a sounding. Sometimes radiosonde or ground equipment problems result in iMetOS reporting many (10 or more) super-adiabatic that relate to problems with the pressure, temperature, relative humidity, or winds data. To solve this problem, some observers arbitrarily delete up to 9/10's of every minute of data for much of the flight so that software will fill in the missing data with interpolated values. The same holds true for the position data. THIS MUST NOT BE DONE! Editing this much data only creates an overly smoothed sounding that is not representative of the true atmosphere. The best course of action when this situation occurs is to terminate the flight at the point where the problems began.

5. Terminate a sounding early if necessary. NWS uses about 75,000 radiosondes each year and a small percentage will not function correctly. Sometimes a radiosonde will provide clearly erroneous temperature or pressure data from the start or later in the flight


Quality Control of Data June 2009 Revision B

7-2

and many data check messages will be displayed. In such cases the sounding must be terminated at the point where the bad data started. If the RH and wind data are erroneous the flight does not need to be terminated. Delete the bad RH and/or winds from the point where the problem occurred to flight termination.

6. Edit the position data. When plots of the position angles versus time are displayed, it’s clear from the erratic data in the plots that the actual lock-on time was later in the flight. If a layer of position data is bad, then delete ALL the position data in the layer. Say it takes a couple of minutes to lock onto the radiosonde at release. Examination of the azimuth and elevation angles plots shows that the angles are erratic until 2.1 minutes into the flight. In such a case, ALL the position data up to 2.1 minutes into the flight must be deleted. No effort must be made to determine which points to keep or delete. If angles become erratic later in the flight, this procedure must also be followed.

7. Examine iMetOS plots of elevation and azimuth angles versus time. Rapid oscillation in the elevation and azimuth angle plots or data spikes indicate that the group equipment is operating below standards. Observers must edit the position data accordingly; inform the electronics technician staff about the problem.

8. Don’t delete good data. NWS has seen soundings where the observer deleted data for no apparent reason. Some observers arbitrarily delete up to 9/10's of every minute of data for much of the flight so that software will fill in the missing data during the minute period with interpolated values. The same holds true for the position data. THIS MUST NOT BE DONE! Editing good data only creates an overly smoothed sounding that is not representative of the true atmosphere.

9. NEVER release a radiosonde into or near a thunderstorm. If a thunderstorm is occurring at the time of balloon release, then the observer MUST wait until the storm passes before releasing the balloon.

Here's why,

a) The observer increases the likelihood of being killed by a lightning strike as he or she proceeds to release the balloon. During a storm, the flight train basically becomes a lightning rod with the observer holding the lower end.

b) The data collected inside or near thunderstorms are mostly garbage and are not useful for weather forecasts. The sounding does not represent the synoptic scale environment and NCEP does not use such soundings for ingestion into numerical weather prediction models. See Figure 7-1 below showing Skew-T plots of radiosonde data collected inside thunderstorms.

c) Thunderstorms typically terminate a flight early owing to balloon icing or strong downdrafts.

NOTE: If the storm persists during the entire release time window, then the observation will be logged as missed. 10. If station staff notice prolonged, data quality problems that persist from month to month, they

must contact the NWS Upper-air Program Manager to help find the cause and troubleshoot the problem.



Figure 7-1: Sounding taken inside a thunderstorm with very erratic temperature data.

7.3 Current USA (other) RAOB “THANKS” Report Under the World Weather Watch program, the WMO has requested that various WMCs and Regional Meteorological Centers (RMCs) assume the responsibility for global monitoring and quality control of specific types of data. The task of coordinating the monitoring of upper-air data has been undertaken by the European Center for Medium-Range Weather Forecasting (ECMWF), located near Reading, England. The ECMWF, along with the major numerical prediction centers throughout the world, monitors the reception and quality of upper-air data from every synoptic network upper-air station in the world. NCEP (Washington D.C., WMC) compiles the U.S. AQC Monthly Quality The centers have the authority for reporting suspected deficiencies to individual upper-air units within their purview. The National Centers for Environmental Prediction (NCEP) alert NWS and CHUAS upper-air units of problems with their observations. The Raob "Thanks" Reports program reports raob data set inventory as of selected quarter hour intervals, especially from 0:45 to 2:00 hours after 00:00 and 12:00 UTC. It is during these intervals that the coded data sets are expected to be disseminated from the stations. Users may use this program to monitor receipt of raob data sets into the NCEP CCS (Central Computing System), where the data must arrive for model ingests and to receive inventorial credit. This program reports in near real time (seldom more than a one minute delay) at the selected quarter hours, which makes it possible for station operators or managers to detect



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possible communications problems, especially if their data sets did not post as expected. Note that all time references are UTC (Coordinated Universal Time, which is equivalent to GMT (Greenwich Mean Time) and Z (Zulu) time.

7.3.1 The Raob "Thanks" Reports program consists of four station groups. The USA (NWS) group consists of United States National Weather Service (NWS) stations including Alaska, Hawaii, Puerto Rico, and Pacific island stations that are NWS sponsored. The USA (other) group consists of blocks 70, 72, and 74 stations that are non-NWS sponsored. These stations are mostly military installations, but can also be sponsored by NASA or other agencies. The Latin America group consists of stations located in Mexico, Central America, South America, Caribbean Islands plus Bahamas and Bermuda. Equivalently, blocks 76, 78, and 80 through 88 comprise this data group. Notice that San Juan (78526) is included in this group as well as the USA (NWS) group. The Canada group consists of all block 71 (Canada) stations. Any block 71 stations located beyond the Canadian provinces and territories are listed last.

7.3.2 Raob data sets are reported as three data subsets or groups. Group A consists of only part TTAA. A station will get capital A ('A') credit for reporting part TTAA with at least two levels of observational data. It is presumed that one level of data will be the surface data. Therefore, an 'A' will be granted for at least one level of observational data aloft. A station will get lower-case A ('a') credit for reporting part TTAA with no observational data. Neither 'A' nor 'a' credit will be granted for a missing TTAA. Group B consists of parts TTBB/PPBB except only TTBB for those stations that report significant wind data within part TTBB. A station will get capital B ('B') credit for reporting at least two levels of data (surface data plus at least one level aloft) including wind data in parts TTBB/PPBB or only part TTBB. A station will get lower-case B ('b') credit for reporting at least part TTBB that contained no observational data or one level of data which presumably was the surface data. Neither 'B' nor 'b' credit will be granted for a missing TTBB. Group C consists of parts TTCC/TTDD/PPDD except only TTCC/TTDD for those stations that report significant wind data within part TTDD. A station will get capital C ('C') credit for reporting at least one level of observational data including wind data in parts TTCC/TTDD/PPDD or only parts TTCC/TTDD. A station will get lower-case C ('c') credit if parts TTAA and TTBB have no data or one level of observational data, and part TTDD came in with no data. However, if part TTAA or TTBB contained more than one level of observational data, and the raob failed to reach 100 hPa (mb), then NWS stations must send all three group C parts with the appropriate codes while all others are required to send only part TTDD that contains no data to get 'c' credit. Otherwise, the station will get neither 'C' nor 'c' credit. Whenever a station has earned all three capital letters (ABC), the denotation 'ABC' will be changed to 'THKS' (THANKS).



Examples: a - group A came in with insufficient data, and groups B and C were missing. AB - groups A and B came in with data, but group C was missing. ABc - groups A and B came in with data, but group C came in with no data. C - group C came in with data, but groups A and B were missing. AbC - groups A and C came in with data, but group B came in with no data. abc - all groups came in but none with sufficient data. THKS - all groups came in with sufficient data. THANKS! http://www.nco.ncep.noaa.gov/pmb/nwprod/thanks/index.thankint.php

7.3.3 Example of “THANKS” NCEP UPPER AIR RECEIPT MESSAGE FOR 20061227 12 UTC: TIME OF EXECUTION Wed Dec 27 14:01:01 UTC 2006 THIS WEBPAGE IS UPDATED EVERY 15 MINUTES FROM 0:45 to 2:00 AFTER 00 and 12 UTC. 76225 THKS 76256 THKS 76382 76394 a 76405 76458 THKS 76526 THKS 76595 76612 76644 THKS 76654 AB 76679 THKS 76692 AB 76723 76743 THKS 76805 78016 abC 78073 78367 78384 ABc 78397 THKS 78486 78526 THKS 78583 THKS 78718 78762 78807 THKS 78866 ABc 78897 THKS 78954 AB 78970 AB 78988 THKS 80001 80035 80222 80398 81405 THKS 82022 A C 82099 82193 a 82244 82281 82332 A C 82397 THKS 82400 THKS 82411 A 82599 ab 82678 THKS 82705 82765 82824 82900 THKS 82917 82965 82983 THKS 83208 83229 THKS 83288 THKS 83362 83378 83498 83525 THKS 83554 83566 THKS 83612 83650 AB 83708 83746 THKS 83779 THKS 83827 83840 83899 83928 83937 83971 84008 84378 84416 84628 85442 ABc 85469 85586 THKS 85799 THKS 85934 THKS 87047 A c 87155 THKS 87344 THKS 87418 87576 87623 THKS 87860 THKS 88889 THKS Group A (TTAA); Group B (TTBB [and PPBB]); Group C (TTCC, TTDD, [and PPDD]). [Some stations report no PPBB/PPDD but report sig wind data in TTBB/TTDD.] THKS means all required parts were in at this time with sufficient data. THANKS! A capital letter means all required parts had data at this time for that group. A small letter means reports received but some part had no data for the group. A space means one or more required parts were missing from the group. This message measures NCEP data receipt and reflects total system throughput. Please retransmit missing reports, but DO NOT MAKE NUMEROUS RETRANSMISSIONS. Check SDM and Gateway administrative messages for news on any comms problems. Reference the "Thanks" Criteria for further details. National Centers for Environmental Prediction (NCEP), Camp Springs, MD (301) 763-4408



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7.4 Spanish Translated THANKS 2 Page Thanks to Danny Foster (Contractor) for having this page translated into Spanish. Reporte actualizado "Thanks 2" de las Observaciones de radiosondeo Observaciones de radiosondeo recibidas en el Centro Nacional de Predicción del medio ambiente (NCEP, siglas en inglés), válidas para el día 30 de junio del 2004 a las 14:00:01 TMG. Esta página es actualizada cada 15 minutos entre las 0:45 y las 02:00 y entre las 12:00 y las 14:00. 76151 76225 THKS 76256 ABc 76394 THKS 76405 THKS 76458 THKS 76526 ABc 76595 a 76612 a 76644 THKS 76654 THKS 76679 THKS 76692 THKS 76723 THKS 76805 AB 78016 THKS 78073 THKS 78355 78367 78384 THKS 78397 ABc 78486 THKS 78526 THKS 78583 78641 78720 78730 78762 THKS 78808 78866 THKS 78897 A 78954 THKS 78970 78988 80001 A 80035 80222 80241 80398 80413 80447 80462 80476 “A” significa que se recibieron los datos del grupo A (TTAA) completos. “B” que se recibieron completos los grupos TTBB y PPBB. La “C” que se recibieron completos los grupos TTCC, TTDD y PPDD. “THKS” significa que se recibió el mensaje completo, con datos en todos sus grupos, para esa hora específica. A, B o C minúscula significan que se recibieron los datos pero están incompletos para ese grupo específico. Espacio en blanco significa que no se recibieron los datos para esa estación en particular. Este mensaje refleja los datos recibidos en el NCEP y el total de los datos procesados por el sistema para esa hora. Por favor retransmita los mensajes no recibidos. REENVÍELOS UNA SOLA VEZ, NO REALICE RETRANSMISIONES REPETITIVAS. Revise SDM y el administrador de mensajes Gateway cuando sospeche que existen problemas de comunicación.

7.5 Raob Data Manual Quality Control Reports The Monthly Raob Data Report of Manual Quality Control is issued as soon as possible after the end of each calendar month. The report is the result of a compilation of entries in the Senior Duty Meteorologist (SDM) daily logs during the specified calendar month with emphasis on entries pertaining to data which were flagged for deletion. Raob stations in the North American region which were most problematic will stand out in this report. The report divides the North American region (raob blocks 04, 70, 71, 72, 74, 76, 78 and also U.S. supported block 91 stations which include Hawaii and Pacific island U.S.A. possessions) into two divisions. The first comprises the conus U.S.A. (blocks 72 and 74), and the second comprises all others ((blocks 04, 70, 71, 76, 78, and 91). For both divisions, the report provides general quantitative information followed by a specific list of stations that had more than three citations during the month. Also, the author will render statements pertaining to trends or possible explanations for the more problematic stations.


Revision B June 2009 8-1 Completion of Documentation

CHAPTER 8 COMPLETION OF DOCUMENTATION (FORMS)

8.1 Introduction Keeping records of CHUAS upper-air sounding performance, flight equipment, and logistics is a key component of WSH Maintenance Logistics and Facilities Branch. This information is used to determine if the station is operated and maintained in accordance with established procedures and to help manage upper air supplies. A number of forms are used to collect this information and this chapter provides information on their completion and submission. It is essential that all upper-air forms are filled in with accurate information and submitted in a timely manner.

8.1.1 Upper-air Forms This chapter covers the completion and submission of the following forms: WS Form B-29 – Rawinsonde Report WS Form B-85 – Rawinsonde Inventory

8.2 Completion and Submission of Forms Currently two upper air forms, WS Form B-29 and WS Form B-85 are completed and submitted to WSH Maintenance Logistics and Facilities Branch. WS Forms B-29 and B-85 are completed using Word or other approved software and sent via email attachment to WSH Maintenance Logistics and Facilities Branch ([email protected])

8.3 WS Form B-29, (Rawinsonde Report) WS Form B-29 is submitted each month. Begin this form with the scheduled 0000 UTC flight on the first day of the month. Flight information should be logged into the form after each observation. However, stations have the option to wait until the end of the month to complete the form, but it must be submitted within two days after the end of the reporting period. CHUAS should prepare an electronic version of WS Form B-29. Send an e-mail attachment to WSH Maintenance Logistics and Facilities Branch. Maintain station version on upper-air computer with each month as a separate file for at least 3 years.

NOTE: WS form B-47 (Rawinsonde Monthly Transmittal) was merged with the WS Form B-29. Completion of WS Form B-47 is no longer required.

8.3.1 Entries on WS Form B-29 Entries on the WS Form B-29 should be made as follows:

A. Station Information - The station name and the four letter station identification number (SID), the name of the person preparing the form, and the form date.

B. Ground and Flight Equipment


Completion of Documentation June 2009 Revision B

8-2

1. Date of last Alignment – Select the date of the last tracking alignment check by the site electronic technician.

2. Orientation Check – Entry should be “Daily”. If this check is not done before each flight indicate reason why in the “Remarks” block.

3. Rejected Balloons – Enter the balloon manufacturing, lot number or date of manufacture, and select reason for rejection. Include in the remarks section balloon type, size, and type of defect for each balloon rejected during the period covered by the report.

C. Unsuccessful Releases - Make entries for all flights released that did not reach 400 hPa. This includes any flights not assigned an ascension number. Whenever entries are made for an unsuccessful release and the cause of the early termination is known, document the problems encountered during the flight. As example, if battery problems were suspected, be sure that all information on the battery is listed. Section F provides information for filling in each entry.

D. Missed and Special Flights

1. Missed Observation – Enter the date, time, and reason when a scheduled observation is not taken. In the remarks section provide additional information on the missed flight and corrective actions made.

2. Special Observation – Enter the date, time of release, and the reason for taking a special. In the remarks section note who requested the special observation (e.g. National Hurricane Center)

NOTE: Special soundings should be assigned an ascension number and sent to NCDC for archival.

E. Station Operation and Equipment Remarks - All other pertinent remarks not included in other sections of the form should be included in this block. Mandatory remarks include:

1. Effective date and time of any change in the upper-air program. This includes instructional changes, change in the type of radiosondes used or the number of routine observations per day, and installation of new upper-air equipment, and equipment modifications are made.

2. Ground equipment problems encountered and corrective actions taken. Whenever a system or a component of a system has been inoperative during the period covered by the report, enter the name of the system or component and dates out of service and back in service.

3. Corrections to entries on any preceding WS Form B-29. A brief, but complete explanation should be included.

4. Continuation of remarks from the remarks section in the Flight Summary section of the form.

F. Flight Summary Information - Make entries in the Flight Summary for each observation that is assigned an ascension number. Flights taken for test purposes would be logged in the Special releases and a note made in the “Remarks” column.



Make entries as follows:

1. Ascension Number (ASCNO) – List each flight that has been assigned as ascension

number. ASCNO 001 will be used for the first successful flight for each year.

2. Date (UTC) – Select the month and day of the observation.

3. Observation (OBS) Time (UTC) – Enter the observation time to the nearest whole hour, UTC; (e.g., “12” would be entered for the 1200 UTC sounding).

4. Radiosonde Serial Number – Enter the complete radiosonde serial number. This includes any letter designation that is part of the radiosonde serial number.

5. Sonde Type – The Radiosonde type for CHUAS is “RDF”.

6. Balloon Manufacturer – Select the appropriate balloon manufacturer.

7. Lot Number or Date of Manufacture – Enter the balloon lot number. If not available, enter the date of balloon manufacture printed on the balloon bag or shipping box.

8. Nozzle lift – Enter the value to the nearest 100 grams or cubic foot.

9. Balloon Ascent Rate – Enter the ascent rate of the balloon from the surface to the 400 hPa level and from the 400 hPa level to flight termination. Enter the values to the nearest meter.

10. RAOB Termination – Select the reason for termination

11. Height – Enter the termination height of the sounding to the nearest meter.

12. Remarks – Enter remarks concerning anything unusual about the flight. If additional space is needed, the remarks should be continued in the Station Operation and Equipment Remarks section.

13. Observer – Enter the initials of the observer who took the observation.

8.4 WS Form B-85, (Rawinsonde Inventory) WS Form B-85 shall be completed promptly at the end of each month. Check all entries for accuracy and submit the form within 2 days of the end of the month. CHUAS should prepare an electronic version of WS Form B-85. Send an e-mail attachment to WSH Maintenance Logistics and Facilities Branch. Maintain station version on upper-air computer with each month as a separate file for at least 3 years.

8.4.1 Entries on WS Form B-85 Entries on the WS Form B-85 must be made as follows:

A. Station Information: The station name, four letter station identification number (SID), and the name of the person preparing the form.

B. Monthly Inventory – Part 1: Columns identified as “Radiosondes and Balloons” are divided into sub-columns. This is for the sites having more than one type of radiosonde or balloon type on station, in such



8-4

instances, separate inventories for each type of radiosonde or balloon is required.

Make the following entries: Line 1 Beginning Balance - Enter the number of radiosondes and balloons.

Line 2 Quantity Received During Month – Enter the number of radiosondes and balloons received during the month.

Line 3 Total Available during Month – The total of line 1 and line 2.

Line 4 Released During Month – Total number of radiosondes and balloons released in the month. This includes the number used for additional releases.

Line 5 Quantity of Serviceable Items Shipped – Indicate the number of serviceable radiosondes or balloons shipped during the month. Indicate in “Remarks” site to which they were shipped.

Line 6 Number of Items Rejected – Number of radiosondes and balloons rejected for whatever reason.

Line 7 Total Used – Total number of radiosondes and balloons used during the month. This is the sum of line 4, line 5, and line 6.

Line 8 Ending Balance – Number of serviceable radiosondes and balloons on hand at the end of the month. This is the difference from line 3 and line 7. Do not include rejected items.

Line 9 Ending Balance – Number of serviceable radiosondes and balloons on hand at the end of the month by actual count. Do not leave this entry blank.

Line 10 Defective Items on Hand – The number of defective radiosondes and balloons on hand at the end of the month.

Line 11 Quantity of Defective Items Shipped – Total number of defective radiosondes and balloons shipped during the month to the National Reconditioning Center (NRC), contact WSH Maintenance Logistics and Facilities Branch ([email protected]) before shipping radiosondes and defective balloons.

Line 12 Surplus Hygristors on Hand – Quantity of usable spare hygristors on hand at the end of the month.

Line 13 Surplus on hand – Quantity of usable spare batteries on hand at the end of the month.

Line 14 Shipment Number – Enter the shipment number taken from the outside of the Radiosonde or balloon box.

C. Supplemental Inventory and Remarks – Part II – Take an end of the month inventory of all supper-air expendables and fill in the appropriate form entries. This includes the count of individual cylinders of lifting gas, lighting units, train regulators or unwinders, parachutes, and rolls of twine. Do not enter quantity of boxes or cases in stock.

D. Flight Summary



Number 2nd Releases – Enter the total number of second balloon releases during the month. Number 3rd Releases – Enter the total number of third releases during the month Number of Special Releases – Enter the number of special releases for whatever reason. Number of Unsuccessful releases and Flights – Enter the total number of releases that did not reach 400 hPa.

Note: This number must be equal to or greater than the total number of 2nd and 3rd releases.

E. Remarks – Include any information about supplies. This includes items missing from a shipment, excessive number of batteries rejected, damage to shipments, and the balloon and Radiosonde type if listed as “other”. Use this space as c continuation sheet for Part I whenever necessary.



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Revision B June 2009 9-1 Station Safety

CHAPTER 9 STATION SAFETY

9.1 Introduction Safety is a vital part of the Upper-Air Program. Each site shall have the required safety equipment and documentation on station. The site supervisor is responsible to ensure that proper safety procedures and practices are being followed. This emphasis on maintaining a safe work environment is especially important at sites using hydrogen or natural gas for inflation.

9.2 Upper-Air Safety Issues inside the Office There are two tasks inside the office that need to be performed to ensure the upper-air program’s safety:

1. A posting of the location of wires, antennas, and other obstructions throughout a 360 degree circle of the launch site. This chart shall be prominently posted by the upper-air workstation inside the office. The station manager shall advise all the staff of the inherent dangers of trying to disentangle a flight train from wires of any kind that carry an electrical current.

2. Preparation of the water-activated batteries should follow the manufacturer’s instructions. Care should be exercised not to allow battery solution to drip or spill on personnel or equipment. If solution should get on the skin or in eyes of the observer, the area should be flushed immediately with clean running water.

9.3 The Upper-Air Inflation Building The upper-air inflation building is where most of the items dealing with safety are based. Responsibility for safety lies with all on-site personnel. A qualified technician shall at a minimum every 6 months check and document a safety check of the equipment to see that it is in safe operating condition and grounded properly. The observers shall do a visual inspection of the inflation building and inflation room prior to and during the inflation process. The site supervisor shall stay alert to issues that need attention and act promptly to ensure problems are resolved.

9.3.1 Generic Safety Issues for All Inflation Sites There are generic aspects with the inflation building that are common to both hydrogen and helium sites. There are also items that pertain strictly to hydrogen sites.

9.3.1.1 Outside the Inflation Building

The following items should be routinely checked outside the inflation building:

1. The area surrounding the inflation building should be clear of obstacles and be level to allow the observer an environment that is safe to launch the balloon.

2. The building when not in use shall have all doors locked to ensure unauthorized persons do not have access to the area.

3. The foot and hand railings should be secure and sturdy. A foot rail or kick plate shall be installed at the top of the stairs leading up to the radome to eliminate the potential of personnel possibly slipping off or falling from the stairs during slippery conditions.

4. All outside lights should work and the area should be well lit.


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5. A communication system is required and should be turned on prior to an individual going out to the inflation building. This is to ensure an open line of communication is kept with the office. This requirement is especially needed for launches during inclement weather and to ensure that if an observer is injured there is a means of calling for help.

6. Overhead doors and louvers must be in good operational condition.

7. Entrance to the stairwell leading to the top of the roof or radome should be either secured or have an “Authorized Personnel Only” sign chained across the stairs.

9.3.1.2 Inside the Inflation Building

The following are required inside the inflation building at all sites:

1. The floor shall be kept clean and free of debris.

2. Approved fire extinguishers shall be placed inside the inflation building and also inside the radome.

3. The inflation table shall be clean and free of dirt.

4. Expendable items stored in the inflation building shall be stored within electrically grounded metal cabinets.

5. The interior of the building shall be well lit.

6. The gas cylinders (any on-site) will be properly marked and secured individually or possibly in pairs to ensure they can not topple over (see Figure 9-1 and 9-2).

7. Cylinders will be pre-positioned to keep personnel from moving cylinders themselves.

8. First-aid kits shall be available in the inflation building, the radome, and the hydrogen generator building.

9. Spare UL approved regulator available.

10. Fill rate follows station instructions.

Figure 9-1: Cylinders Secured in Group


Revision B June 2009 9-3 Station Safety

Figure 9-2: Cylinders Secured in Pairs

9.4 Hydrogen Sites The Proton Hydrogen Generator model 4x100 1058 was replacement for the Stuart generator. There are two models “A” and “B” in the CHUAS. The following rules apply to sites using hydrogen or natural gas:

1. Only spark-proof tools shall be used in and around a hydrogen environment. Brass tools are available through NLSC.

2. No smoking or lighting of flammable materials shall be allowed within 25 feet of buildings where hydrogen gas is stored or generated. Each site shall have signs prominently displayed on the exterior of each side of the inflation building saying “Danger Hydrogen – No Smoking With-in 25 Feet”. These metal signs may be obtained through NLSC using ASN P810-3.

3. All overhead door runners shall be electrically grounded. Grounding can be accomplished by using a grounding wire and connecting it to a nearby grounding rod. The rollers should have a conductive lubricant applied at frequent intervals.

4. The hydrogen fill system including the inflation hose, nozzle, and inflation table shall all be grounded with the frame of the building and have a resistance of less than 25 ohms. (Resistance shall be checked at least every 6 months by a qualified technician.)

5. An anti-static mat shall be placed at the end of the inflation table where the observer stands during the process of attaching the balloon to the nozzle and tying of the balloon after inflation.


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6. Safety posters shall be prominently displayed in the inflation room and cylinder storage area. These posters or signs are available through NLSC. The ASN range P810-4A through P810- 4E. The entire set of 5 posters may be ordered using ASN P810-4.

a. P810-4A - General rules for hydrogen fire prevention

b. Safety rules for hydrogen cylinders

c. P810-4C - Balloon rupture procedures

d. P810-4D - Hydrogen-fed fires

e. P810-4E - Non-hydrogen Fire

7. New personnel shall not be allowed to work in and around hydrogen generators unless accompanied by a qualified operator. Each operator must be certified prior to working alone.

8. Only a minimal amount of expendables shall be stored inside the inflation building. Any combustible expendables shall be placed within a metal storage cabinet.

9. At least 2 fire extinguishers shall be placed in the inflation room. One of extinguishers shall be at least 20 lbs and be placed near the exit. Additional 10 lb or larger extinguishers shall be placed in the cylinder storage area and in the radome. The extinguishers shall be inspected annually.

10. Vents in the inflation building shall be placed near the top of the inflation building and should be at a minimum of at least 1 square foot for each 1,000 cubic feet of space within the inflation building.

11. Trash cans shall be kept outside the inflation building. They should be metal and have a lid securely in place.

12. In the event of a balloon rupture, the observer shall carefully open the side door and the overhead door at least 18 inches to allow the area to ventilate properly. The observer should then walk outside the building and wait 15 minutes prior to beginning to fill another balloon.

9.5 Safety Issues Prior to Release The following should be followed prior to launching a balloon:

1. At sites located within 5 nautical miles of any active runway for a controlled airport will contact the controlling authority and request permission to do a balloon release.

2. At all sites, the observer will check the horizon to ensure there are no aircraft or other activity that the balloon might interfere with or endanger. If aircraft or any other activity is present, the observer will postpone the launch until it is safe to launch.


Revision B June 2009 10-1 Special Inflight Situations

CHAPTER 10 SPECIAL INFLIGHT SITUATIONS

10.1 Introduction Radiosonde flights may encounter numerous problems that require close attention by the operator. Any flight with special problems shall have the (iMetOS and NWS) standard archive files saved on diskettes and set aside for further evaluation. Send the data files to the NWS Upper-Air Program Office for further evaluation, a statement of what happened along with pertinent plots to help illustrate the problem (see section 9.3). It is impractical to capture each unusual flight occurrence, but some of the most common occurrences follow.

10.2 Descending and Re-ascending Balloon The descending/re-ascending balloon situation may occur with icing, severe turbulence, or due to a balloon being under-inflated. It is the observer’s responsibility to look closely at the data to ensure the flight should be allowed to continue or be terminated. The key to making this decision is looking at the data and seeing if data following the occurrence looks reasonable and compares with a previous sounding or those of nearby stations. (See Figure 10-1 and Figure 10-2) Key indicators include:

• Irregular pressure profile plot

Figure 10-1: Pressure Profile Indicating Fluctuations If Figure 10-1 is zoomed in at the locations showing a wave in the pressure profile and the processed tabular data is displayed. A definite slowing of the ascension rate and heights is found. (See Figure 10-2 and Figure 10-3)


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Figure 10-2: Pressure Plot with Processed Data Indicating Slowing of Ascent at Base of

Wave Beginning at Minute 9



Figure 10-3 indicates a more significant wave in the pressure profile and a more abrupt change in the ascent rate being noted beginning just prior to minute 44 and again after minute 50.

Figure 10-3: Pressure Waves at Minutes 43 and 51 with processed Data Indicating Temporary Negative Ascent Rates



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10.3 Erratic Temperatures and Relative Humidity Profile There may be occasions when the temperature and relative humidity readings show erratic data. The primary tools for finding problems with the radiosonde’s data are to look at the Temperature and RH data plots. (See Figure 10-4 and Figure 10-5) Erratic data may be indicated on the Temperature or Temperature and RH plots by either an abrupt shift in the plot or by continual shifts in the plotted data. (See Figure 10-5, Figure 10-6, and Figure 10-7) NOTE: Review the appropriate plot considered erratic to ensure levels are not selected from the questionable data

Figure 10-4: Temperature and RH Plot Showing Erratic Data

The plotted temperature and RH data shows a zigzag and widening of the temperature profile beginning just prior to 30 minutes into the flight. Going back and investigating the various parts of the flight by zooming in on those areas with temperature call-ups illustrates clearly that a problem with the temperature is evident by the deviations over a short time span. (See Figure 10-5 and Figure 10-6)



Figure 10-5: Temperature Plot Indicating Erratic Data 25 to 41 Minutes

Figure 10-6: Temperature Plot with Erratic Data from 85 to 90 Minutes

NOTE: Holding the hygristor, take caution not to touch the coating. If the coating is touched, the hygristor must be rejected



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NOTE: A second release may not be necessary for bad RH data, unless the RH data is considered essential The plotted data the coded messages will reflect the abrupt shifts by coding levels close together with significant temperature changes. (See Figure 10-7)

Figure 10-7: TTDD Message with Abrupt Temperature Shift

A significant temperature change can be seen in the 4th line of the coded message. The temperature at 20.3 hPa is -59.3 degrees and the temperature at 20.1 hPa is -56.9 degrees and 2.4 degree change which is an extreme change over such a small amount of time. The height difference for these two levels is only 80 meters. (See Figure 10-8)

Figure 10-8: WMO Levels Showing Unrealistic Temperature Change Over 80 Meters

10.4 Erratic Wind Data The observer must also look closely at the wind plot to decide if the plotted data looks realistic. (See Figure 10-9)



Figure 10-9: Wind Plot Showing 24 Knot Wind Speed Change from Minute

78 to 80 and Direction Change of 75 Degrees from Minute 77 to 79 Another way to tell if the wind data is questionable is by looking at the coded messages. (See Figure 10-10)

Figure 10-10: Winds Above 100 hPa Indicate 24 Knot Speed Change from Height 77 to 79

10.5 Data Dropouts Data dropouts may occur with any or all of the sensor elements. The primary tool for identifying this problem is looking at data plots. Data plots show a radical departure from readings both before and after the data dropout. (See Figure 10-11 and Figure 10-12)



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Figure 10-11: Data Dropout Illustrated by Dewpoint Dropout

After identifying or recognizing a data dropout the operator should expand the plotted area to find the beginning and ending points of the data dropout. (See Figure 10-12)

Figure 10-12: Expanded View of Dewpoint Dropout



Go to the Processed Data and locate the data dropout area. (See Figure 10-13)

Figure 10-13: Processed Data with Dropouts in Dewpoint and Height Data

The WMO coded message (TTBB) indicates the data dropout in the dewpont depression at 378 hPa and 376 hPa. Notice the dewpoint depression for the level at 387 hPa was 58 or -08 degrees less than the temp and the level following the 376 hPa level is 89 or -39 degrees less than the temperature at that level. (See Figure 10-14)

Figure 10-14: TTBB Message with Levels Showing Dewpoint Depression Dropout

The observer should mark the data points with data dropouts and “Apply User Edits” to have the data interpolated. (See Figure 10-15 and Figure 10-16) CAUTION: Be sure to “Left Click and Drag” the mouse over the entire area to be “Marked”. Clicking on each individual point may miss points and does not work if the configuration has been changed from data points each second



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Figure 10-15: Marked Data Prior to Applying User Edits

Figure 10-16 shows the marked data after applying “User Edits”. The missing data is now interpolated.

Figure 10-16: Marked Data After Applying User Edits



Figure 10-17 shows the TTBB message after applying “User Edits” notice the levels at 378 and 376 hPa are gone and there is no dewpoint depression for any of the levels at or near 00 at the point in the flight.

Figure 10-17: TTBB Message after Applying User Edits Levels with 00 Dew point

Depression Gone

10.6 Inaccurate Relative Humidity above Surface Layer The relative humidity sensor at times may indicate significantly lower readings immediately off surface due to poor initial aspiration through the humidity duct and usually last for less than a minute. NOTE: The RH sensor has a dry bias that may show relative humidity readings as low as 1% between layers early in the flight. Care should be taken in editing this data. The readings may be as much as 10% too low, but should not be edited unless found to be totally off from other meteorological products such as water vapor imagery or previous or surrounding sounding data. Paragraph 10.7 provides additional details.

Figure 10-18: Relative Humidity Indicates Unrealistic Drying Immediately Off Surface



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Go into the Processed Data and “Mark” by clicking the left mouse button and dragging from the first data point above surface until a more representative readings is reached. Then “Apply User Edits”. (See Figure 10-19 “Before Marking” and Figure 10-20 “After Marking”)

Figure 10-19: Processed Data and Relative Humidity Plot Before Marking Data

The Relative Humidity plot should indicate a more representative picture of the atmosphere. Notice the difference between the “Raw Data” and the “Corrected Data”. (See Figure 10-20)

Figure 10-20: Processed Data and Relative Humidity Plot After Marking Data



10.7 Relative Humidity Dry Bias and Environmental Conditions The Sippican humidity sensor has been found to have a dry bias. The sensor has limitations, if the sensor is exposed to a moist cloud layer and then ascends into a cloud free area, and readings may be off by as much as 15%. This is a result of hysterias or a lag the sensor has in its ability to recover to actual conditions. In a non-changing or stable environment with temperatures warmer than -10 degrees Celsius, the relative humidity values normally are within 3 to 5%. Also complicating this issue are the occasions with extremely low relative humidity in lower portions of the atmosphere. (See Figure 10-21 and Figure 10-22) Notice in Figure 10-21 from around 850 to 400 hPa the relative humidity is less than 10% from the Chilled Mirror. The Chilled Mirror Humidity sensor readings are considered the standard for moisture accuracy. Finally, notice these soundings are from Wallops Island, VA., which is a coastal location.

Figure 10-21: Relative Humidity Standard Indicates Extremely Dry Layers near Surface



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Figure 10-22 also provides another example of the chilled mirror indicating very dry conditions in the lower portions of a flight with some layers having relative humidity well below 10%.

Figure 10-22: Chilled Mirror RH Readings Below 10%



The humidity sensor will indicate dry areas in the atmosphere that are known to be at times lower than the actual true conditions, but having readings with a 10% to 15% difference is typically a much better condition than making the data missing. (See Figure 10-23) Editing or deleting relative humidity data at temperatures warmer than -35 degrees Celsius should not attempted unless the observer is absolutely sure from other meteorological products that the data is invalid. Above the tropopause, in the stratosphere, relative humidity values of greater than 10 to 15% are not likely in most cases except for thunderstorm penetration in the stratosphere. Deleting obviously moist RH profiles will not cause problems for the RRS software. The RRS software will use a default RH value of 20% for missing or deleted data. However, the coded messages will show missing dewpoint depressions that may trigger some errors in certain plot programs.

Figure 10-23: Dry Slots from 13 to 40 Minutes and above 75 Minutes

NOTE: When the plot indicates dry slots, be sure to validate the data with other products. If the data is definitely bad, delete it. Otherwise, do not edit.

10.8 Inaccurate Release Detection The RRS software recognizes balloon release by detecting a decrease in pressure. There are certain conditions that may cause the release detection to be early or late. A few are:

• Abrupt Change in Pressure

• Change in Frequency

• Radiosonde Failure

• Equipment Failure A change in pressure may cause the software to detect an early or late release. This may occur



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during transport to the inflation building. A change in frequency of only .2 MHz may cause the signal to be lost and release may not be detected. Radiosonde or equipment failures are also possible points of failure. The key to minimizing this problem is: 11. The operator must verify the frequency and sensor readings during baseline, after baseline,

and prior to going to the inflation building.

NOTE: The observer can not validate the sensor performance at the inflation building, but he/she can check the frequency, signal strength, and the operation of the equipment. 12. It is critical that the frequency and signal strength be verified at the release point prior to and

immediately after release.

Figure 10-24 shows a flight where the release was not detected until 5 minutes after actual release. The surface pressure was 1005.7 hPa and at .33 minutes into the flight the received PTU shows a pressure of 843.9 hPa. The receiver shifted off frequency by only .4 MHz and lost signal. The operator noticed the problem and locked back on frequency. Once the receiver locked back on frequency, the release was detected. The first .3 minutes after release detection had missing “Raw” PTU data and the software interpolated the “Processed” data from surface to the first good data point. Interpolation occurred because less than 1-minute of missing data was recognized.

Figure 10-24: Processed and Raw Data for Flight with Late Release Detection

Figure 10-25 further illustrates the late release detection in the WMO Levels Table and the Pressure plot showing an abrupt change in pressure within the first .3 of a minute. Again, the shift in frequency prior to launch caused the release to go undetected. In this example, the release was detected late, but no data was available because the receiver was off frequency at the true release time. The flight should be terminated because more than 3 consecutive minutes of data were missing. NOTE: If a release is detected early and the data is available in the “Received PTU” Tabular Display, the observer would look at the “Raw” data and find the point where the pressure shows a continual decrease.



Figure 10-25: WMO Levels and Pressure Plot for Flight with Late Release Detection

10.9 Sensor Failure Sensors may fail for various reasons from having defects to being damaged during a launch. The RRS software will terminate a flight once 3 consecutive minutes of missing temperature data is observed, but if data is received the flight will code the data received. This data may be totally unrealistic. It is the observer’s responsibility to use the tools provided to ensure the data is reasonable prior to transmitting the coded messages. Figure 10-6 illustrates a temperature sensor failure. The data received above surface shown in the Processed Data Tabular Display is well beyond possible environmental conditions. The Check Messages should be looked at for significant Temperature Lapse Rate changes over periods of time that exceed 1 minute in duration. Again, it is important to remember that unless the operator “Marks” the Processed Data, the coded message will be generated with the bad data. The TTBB message in Figure 10-7 illustrates the software’s inability to recognize unrealistic values. Notice, the first significant level above the surface has a temperature of -98.3 degrees C.

Figure 10-26: Temperature Sensor Failure Display



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NOTE: The point is that even with modernization of the upper-air tracking system, radiosondes, and software capabilities the operator still has the responsibility to ensure his/her observation is accurate. The system can not detect all deficiencies.

10.10 Leaking Pressure Cell Occasionally a pressure cell will begin to leak and begin to provide extremely high geopotential heights or much lower pressure values than normal. There are several items to confirm this situation exists and then to determine at what point the flight should be terminated. Figure 10-27 provides a look at the Processed Data Set and the Pressure Profile.

Figure 10-27: Leaking Pressure Cell Causing Unrealistic Height and Pressure Values

Some of the key signs of a Leaking Pressure Cell are very unrealistic Ascent Rates and Geopotential Height Values at termination. Notice the Processed Tabular Display indicates at 60.37 minutes elapsed time 54,314 geopotential meters. Remember, a typical flight may reach 30,000 meters or possibly as high as 33,000 meters any flights above 33,000 meters should be looked at closely. NOTE: A typical flight should ascend on average of 300 meters/minute or 5 meters per second. Looking in the ascent rate column that shows values of meters per second any values above 450 meters/minute or 8 meters per second for periods of a minute or more should be reviewed closely with the idea of terminated the flight prior to these unrealistic ascent rates.

10.11 Wetbulb Effect or Evaporative Cooling It is not unusual for a sounding to show significant cooling of the temperature sensor after passing through a cloud or very moist parcel of air into a dry portion of the sounding. The temperature sensor if affected by evaporative cooling will indicate readings cooler than the actual atmospheric conditions. The operator should verify super-adiabatic lapse rates for this condition and mark through the data over a long enough period of time to smooth or interpolate the temperature readings. (See Figure 10-28 and Figure 10-29) Whenever the sounding indicates a moist layer with a significant dry layer above it, evaporative



cooling may occur. If a super-adiabatic lapse is shown during this period, the observer must take corrective action by marking the data. Notice in the example, at approximately 18 minutes in the flight, the RH went from near 70% to 15% in less than 30 seconds. Notice the temperature profile shows a distinct shift to the left towards colder temperatures as well during this time. Looking at the Temperature Lapse Rate column in the Processed Tabular Display is an excellent tool to pinpoint the changes in the temperature data.

Figure 10-28: Wetbulb Effect or Evaporative Cooling Before Applying User Edits

NOTE: The flight data has been captured to show the original Check Messages, Temperature/RH Plot and Tabular Display with a portion of the Temperature Data selected for Marking.



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Figure 10-29: Wetbulb Effect Eliminated After Marking Temperature Data

NOTE: This Exhibit shows the changes made to the Check Messages and the Temperature Data in the Temperature/RH Plot after “Applying User Edits” to the Processed Tabular Data Display.

10.12 Evaluating Flight Termination Point It is the observer’s responsibility to ensure the correct termination point and reason is chosen. There are several key elements the observer should use to ensure this. The key elements include observing the Status Messages, looking at a zoomed in view of the Pressure and Temperature plots, and also the processed data set in around the termination point to ensure maximum height has been selected. (See Figure 10-30)



Figure 10-30: Expanded Temperature Plot at Termination

The temperature and pressure plot are always good starting points to verify the proper termination point and reason has been chosen. In Figure 10-30 notice the large temperature shift after 96.4 minutes. The Pressure plot shows the termination point by an abrupt deviation from the trend. Note after 96.35 minutes the trend suddenly changes abruptly to the right indicating a sudden increase in the pressure. The point of change indicates Balloon Burst. (See Figure 10-31)

Figure 10-31: Expanded Pressure Plot at Termination



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Finally, the Processed Data Set may also be looked at to verify the proper point of termination by looking at the height values and ensuring the point of termination selected coincides with the highest height value. (See Figure 10-32)

Figure 10-32: Processed Data with GPH Heights

10.13 Pressure Increase since Baseline It is extremely important that the surface observation be updated after release. The pressure can have a very significant effect on the data immediately above the surface. If the pressure rise is as little as .3 hPa or 01 inches, and is not updated in the surface observation, a significant super off the surface will be indicated. The Pressure Plot will also show an unrepresentative deviation towards higher pressure. (See Figure 10-33)

Figure 10-33: Pressure Increase since Baseline and Not Updated in Surface Observation


Revision B June 2009 11-1 Clouds and Weather Codes

CHAPTER 11 CLOUDS & WEATHER CODES

11.1 Introduction This chapter provides the necessary tables and specific instructions to enter Clouds/Wx at the Surface Data screen. This guidance assumes no previous knowledge of synoptic code procedures. However, a basic understanding of clouds and weather is necessary. For those already familiar with synoptic code, you will notice some departure from conventional WMO coding procedures. If you simply observe the elements requested and report them according to tables provided in this text, the intent of the Clouds/Wx entry will be fully met.

11.2 Getting Started The Cloud/WX entry is a nine-digit, mandatory group. All nine digits must be entered, regardless of the presence or absence of clouds or significant weather conditions. The WMO format for entry of clouds and weather has been modified to meet NCDC requirements. All stations will follow this modified format, regardless of location; i.e., stations in either WMO Region IV or WMO Region V. A description of the nine digit format follows: Clouds/Wx group format: NhCLhCMCHWWWW

a. Nh = Amount (in oktas) of the sky covered by all low clouds (CL) observed or the amount of sky covered by all the middle clouds (CM) observed. In no case will the amounts of the low and middle clouds be combined to report Nh. Use Table 13-1 to report the amount of low or middle cloud coverage.

b. CL = Type of low cloud, based on the priority given in Table B-2. A solidus (/) is reported if CL clouds are not visible owing to fog or similar obscuring phenomena.

Note: Clouds are divided into three families, classified as low, middle, or high. The general height ranges for these are: surface to 6500 feet for low; 6500 feet to 20000 feet for middle; and above 20000 feet for high. Remember, these ranges are not absolute, but given as a guide only. More consideration may be given to the cloud form than the height in many cases. Each cloud family is coded with a single digit, 0 through 9. The code figure 0 is used to indicate that clouds are not present for a given family.

c. h = Height of the base of the lowest cloud observed. The height reported is with respect to the surface. The height is coded as a solidus (/) if there is a total surface-based obscuration that prevents an observation of the clouds. Use Table 13-3 for the cloud base height.

d. CM = Type of middle cloud, based on priority given in Table 13-4. A solidus (/) is reported if CM clouds are not visible owing to fog or similar obscuring phenomena, or because of a continuous layer of lower clouds.

e. CM = Type of high cloud, based on priority given in Table 11-5. A solidus (/) is reported if CH clouds are not visible owing to fog or similar obscuring phenomena, or because of a continuous layer of lower clouds.


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f. WWWW = Present weather coded in two groups of WW. These code groups are found in Table 11-6. The coding starts with 99 (the highest priority) and descends to 00 (the lowest priority). Note that code figure 17 is placed out of numerical sequence to highlight its relative coding priority. You should note that present weather codes for some weather phenomena are events that have occurred during the past hour, not at observation time. When entering WWWW, go down Table 11-6 and use the first and second applicable code figures. Note that two WW groups must always be coded, even if that means using the same code figure twice. (See the Example Observations page at the end of Chapter 11)

11.3 Amount of Low/Middle Cloud

Table 11-1: Amount of Low/Middle Cloud, Nh Code Figure Cloud amount in oktas (eights) Cloud amount in tenths 0 0 0 1 1 okta or less, but not zero 1/10 or less but not zero 2 2 oktas 2/10 – 3/10 3 3 oktas 4/10 4 4 oktas 5/10 5 5 oktas 6/10 6 6 oktas 7/10 – 8/10 7 7 oktas or more, but not 8 oktas 9/10 or more but not 10/10 8 8 oktas 10/10 9 Sky obscured by fog and/or other meteorological phenomena / Cloud cover is indiscernible for reasons other than fog or other

meteorological phenomena, or observation is not made Note: If there are any breaks in the sky at all, such as an overcast with a mackerel sky (altocumulus perlucidus or stratocumulus perlucidus), Nh would be encoded as 7. If there are only a few patches of low or middle cloud in the sky, Nh cannot be encoded as 0 but is encoded as 1. A partial obscuration does not affect the coding of Nh. A total obscuration is coded as 9, not 8 (overcast sky).

11.4 Coding of Low Cloud Table 13-2 presents the specifications for type of low cloud, CL, in order of priority. Go down the table and use the first applicable code figure.

Table 11-2: Coding of Low Cloud, CL

Code Figure Coding Criteria (a) Cumulonimbus present, with or without other CL clouds

CL = 9 If the upper part of at least one of the cumulonimbus clouds present is clearly fibrous or striated, use CL = 9.

CL = 3 If the upper part of none of the cumulonimbus clouds present is clearly fibrous or striated, use CL = 3.

(b) No cumulonimbus present



CL = 4 If stratocumulus formed by the spreading out of cumulus is present, use CL = 4.

CL = 8 If the CL code figure 4 is not applicable and if cumulus and stratocumulus clouds with bases at different levels are present, use CL =8.

CL = 2 If the CL code figures 4 and 8 are not applicable and if cumulus clouds of moderate or strong vertical extent are present, use CL = 2.

CL = 1 If the CL code figures 4, 8, and 2 are not applicable: use CL= 1, if the CL clouds present are predominantly1 cumulus with little vertical extent and seemingly flattened or ragged cumulus other than of bad weather2, or both;

CL = 5 Use CL = 5, if among the CL clouds present, stratocumulus other than that formed by the spreading out of cumulus is predominant;

CL = 6 Use CL = 6, if the CL clouds present are predominantly stratus in a more or less continuous sheet or layer, or in ragged shreds (other than ragged stratus of bad weather), or both;

CL = 7 Use CL = 7, if the CL clouds present are predominantly pannus (ragged shreds of stratus of bad weather or ragged cumulus of bad weather), or both.

0 No CL Clouds -- No cumulus, cumulonimbus, stratocumulus, or stratus. / CL clouds not visible owing to fog or similar obscuring phenomena. Notes: 1. Consideration of predominance is restricted to the clouds corresponding to CL code figures 1, 5, 6 and 7, which have the same priority. Clouds of any one of these four specifications are said to be predominant when their sky cover is greater than that of the clouds of any of the other three specifications.

2. Bad weather' denotes the conditions which generally exist during precipitation and a short time before and after.

11.5 Height of Cloud Base above Ground

Table 11-3: Height of Cloud Base above Ground, h

Code Figure Reportable Heights (ft) 0 0 to 100 1 200 to 300 2 400 to 600* 3 700 to 900* 4 1000 to 1900* 5 2000 to 3200* 6 3300 to 4900* 7 5000 to 6500* 8 7000 to 8000** 9 8500 or higher or no clouds / Unknown or base of clouds below surface of station

* reported in 100 foot increments ** reported in 500 foot increments

Note: This group is used to report the height of the base of the lowest cloud seen, regardless of



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Cloud amount. The height reported is with respect to the surface. The lowest cloud height is coded with a solidus (/) if there is a total surface-based obscuration that prevents an observation of the clouds.

11.6 Coding of Middle Cloud Table 14-4 presents the specifications for type of middle cloud, CM, in order of priority. Go down the table and use the first applicable code figure.

Table 11-4: Coding of Middle Cloud, CM

Code Figure Coding Criteria (a) Altocumulus present

CM = 9 If the sky is chaotic, use CM = 9. CM = 8 If the CM code figure 9 is not applicable and if altocumulus with sprouting

in the form of turrets or battlements or altocumulus having the appearance of small cumuliform tufts is present, use CM = 8.

CM = 7 If the CM code figures 9 and 8 are not applicable and if altostratus or nimbostratus is present together with altocumulus, use CM = 7.

CM = 6 If the CM code figures 9, 8, and 7 are not applicable and if altocumulus formed by the spreading out of cumulus or cumulonimbus is present, use CM = 6.

CM = 5 If the CM code figures 9, 8, 7, and 6 are not applicable, and if the altocumulus present is progressively invading the sky, use CM = 5.

Note: There are several definitions of CM = 7 and each has a different priority; therefore CM = 7 appears several times in this code table. CM = 4 If the CM code figures 9, 8, 7, 6, and 5 are not applicable and if the

altocumulus present is continually changing in appearance, use CM = 4. CM = 7 If the CM code figures 9, 8, 6, 5, and 4 are not applicable and if the

altocumulus present occurs at two or more levels, use CM = 7. CM = 7, 3 If the CM code figures 9, 8, 6, 5, and 4 are not applicable and if the

altocumulus present occurs at one level, use CM = 7 or 3 depending on whether the greater part of the altocumulus is respectively opaque or semi-transparent.

(b) No altocumulus present CM = 2 If nimbostratus is present or if the greater part of the altostratus present is

opaque, use CM = 2. CM = 1 If there is no nimbostratus and if the greater part of the altostratus present is

semi-transparent, use CM = 1. 0 No CM Clouds -- No altocumulus, altostratus, or nimbostratus. / CM clouds not visible owing to fog or similar obscuring phenomena, or

because of a continuous layer of lower clouds.

11.7 Coding of High Cloud Table 14-5 presents the specifications for type of high cloud, CH, in order of priority. Go down the table and use the first applicable code figure.



Table 11-5: Coding of High Cloud, CH

Code Figure Coding Criteria CH = 9 If cirrocumulus is present alone or is more than the combined sky cover of

any cirrus and cirrostratus present, use CH = 9. (a) Cirrostratus present

CH = 7 If the cirrostratus covers the whole sky, use CH = 7. CH = 8 If the cirrostratus does not cover the whole sky and is not invading the

celestial dome, use CH = 8. CH = 6 If the cirrostratus is progressively invading the sky and if the continuous

veil extends more than 45 degrees above the horizon but does not cover the whole sky, use CH = 6.

CH = 5 If the cirrostratus is progressively invading the sky but the continuous veil does not reach 45 degrees above the horizon, use CH = 5.

(b) CH = 9 not applicable and no cirrostratus present CH = 4 If the cirrus clouds are invading the sky, use CH = 4. CH = 3 If the CH code figure 4 is not applicable and if dense cirrus which originated

from cumulonimbus is present in the sky, use CH = 3. CH = 2, 1 If the CH code figures 4 and 3 are not applicable:

Use CH = 2, if the combined sky cover of dense cirrus, of cirrus with sproutings in the form of small turrets or battlements and of cirrus in tufts is greater than the combined sky cover of cirrus in the form of filaments, strands or hooks; Use CH = 1, if the combined sky cover of cirrus in the form of filaments, strands or hooks is greater than the combined sky cover of dense cirrus, of cirrus with sproutings in the form of small turrets or battlements and of cirrus in tufts.

0 No CH Clouds -- No cirrus, cirrostratus, or cirrocumulus. / CH clouds not visible owing to fog or similar obscuring phenomena, or

because of a continuous layer of lower clouds

11.8 Coding of Present Weather Table 14-6 presents the specifications for present weather, WW, in order of priority. Go down the table and use the first and second applicable code figures. The code figure with the higher priority is reported as the first WW group and the code with the lower priority is the second WW group. (This convention is followed even if the higher priority code describes weather that occurred during the preceding hour but not at the time of observation.) Note that two WW groups must always be coded, even if that means using the same code figure twice. (See the Example Observations page at the end of Appendix B.)

Table 11-6: Coding of Present Weather, WW

Code Present Weather WW = 99-50 Used for precipitation at the station at the time of observation. WW = 99-80 Used for showery precipitation or precipitation with current or recent



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thunderstorms. 99 Thunderstorm, severe, with hail, small hail, or snow pellets at time of

observation. There may or may not also be rain or snow or a mixture of rain and snow of any intensity

98 Thunderstorm at time of observation combined with duststorm at time of observation. There must also be some sort of precipitation at the time of observation, but it may not be seen because of poor visibility. Judgment must be used.

97 Thunderstorm, severe without hail, small hail, or snow pellets but with rain and/or snow at time of observation. The rain or snow may be of any intensity.

96 Thunderstorm with hail, small hail, or snow pellets at time of observation. There may or may not be rain or snow or a mixture of rain and snow of any intensity.

95 Thunderstorm without hail, small hail, or snow pellets, but with rain and/or snow at time of observation.

WW = 94-91 Used if there was a thunderstorm during the past hour, and there is some sort of precipitation at the time of observation. In order to have this situation, the last lightning or thunder observed must have been more than 15 minutes before the observation, but less than 1 hour 15 minutes before the observation. 94 Moderate or heavy snow or rain and snow mixed or hail, small hail, or snow

pellets at time of observation. Thunderstorm during previous hour but not at time of observation.

93 Light snow or rain and snow mixed or hail, small hail, or snow pellets at time of observation. Thunderstorm during previous hour but not at time of observation.

Table 11-6 Coding of Present Weather, WW (Continued)

Code Present Weather 92 Moderate or heavy rain at time of observation. Thunderstorm during previous

hour but not at time of observation. No other forms of precipitation.

91 Light rain at time of observation. Thunderstorm during previous hour but not at time of observation. No other forms of precipitation.

WW = 90-80 Used to report showery precipitation that is not associated with a thunderstorm. Showers fall from cumuliform clouds that are, by nature, isolated. Because of this, individual showers do not last very long. Code figure 89 is not reported under United States rules. 90 Moderate or heavy shower(s) of hail, with or without rain or rain and snow

mixed, not associated with thunder. WW = 88-87 Used if showers of snow pellets or ice pellets are observed at the station at the time of the observation. The snow pellets or ice pellets may or may not be mixed with rain or both rain and snow 88 Moderate or heavy shower(s) of snow pellets or small hail, with or without rain

or rain and snow mixed. All of the precipitation must be moderate or heavy.



87 Light shower(s) of snow pellets or small hail, with or without rain or rain and snow mixed. All of the precipitation must be light.

WW = 86-85 Used if only snow showers are observed at the station at the time of observation. 86 Snow shower(s), moderate or heavy. 85 Snow shower(s), light. WW = 84-83. Used if mixed rain showers and snow showers are observed at the station at the time of observation. 84 Moderate or heavy shower(s) of rain and snow mixed. Intensity of either may be

moderate or heavy. 83 Light shower(s) of rain and snow mixed. Intensity of both must be light. WW = 82-80. Used to report rain showers at the time of observation. 82 Violent rain shower(s).

Report a rain shower as violent if the rate of fall is at least 1.0" per hour or 0.10" in 6 minutes.


Code Present Weather 81 Moderate or heavy rain shower(s). 80 Light rain shower(s).

WW = 79-50 Use code figures 79-50 for precipitation that is not showery. WW = 79-70 Use code figures 79-70 to report solid precipitation not in showers. WW = 79-76 Use code figures 79-76 to report types of solid, non-showery precipitation. 79 Ice Pellets.

Use this code figure regardless of the intensity of the ice pellets and regardless of whether the ice pellets are mixed with another type of precipitation.

78 Isolated star-like snow crystals with or without fog or ice fog. 77 Snow grains with or without fog or ice fog.

Use this code figure regardless of intensity. 76 Diamond dust (ice crystals) with or without fog or ice fog. WW = 75-70 Use code figures 75-70 to report snow that is not in the form of showers at the station at the time of the observation. The code figure selected depends on a combination of intensity and whether the snow is intermittent or continuous. 75 Continuous fall of snowflakes, heavy at time of observation. 74 Intermittent fall of snowflakes, heavy at time of observation. 73 Continuous fall of snowflakes, moderate at time of observation. 72 Intermittent fall of snowflakes, moderate at time of observation. 71 Continuous fall of snowflakes, light at time of observation. 70 Intermittent fall of snowflakes, light at time of observation. WW = 69-60 Code figures 69-60 are generally used to report rain. WW = 69-66 Use code figures 69-66 to report liquid precipitation that is mixed with snow or is freezing. 69 Rain or drizzle and snow, moderate or heavy. 68 Rain or drizzle and snow, light. 67 Rain, freezing, moderate or heavy.



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66 Rain, freezing, light. Table 11-6 Coding of Present Weather, WW (Continued)

Code Present Weather WW = 65-60 Use code figures 65-60 to report rain (but not freezing rain or rain mixed with snow) at the station at the time of observation. The code figure used depends on the combination of intensity and whether the precipitation is intermittent or continuous. 65 Rain, not freezing, continuous, heavy at time of observation. 64 Rain, not freezing, intermittent, heavy at time of observation. 63 Rain, not freezing, continuous, moderate at time of observation. 62 Rain, not freezing, intermittent, moderate at time of observation. 61 Rain, not freezing, continuous, light at time of observation. 60 Rain, not freezing, intermittent, light at time of observation. WW = 59-50 Use 59-50 to report drizzle. WW = 59-56 Drizzle mixed with rain, or freezing drizzle. 59 Drizzle and rain, moderate or heavy. 58 Drizzle and rain, light. 57 Drizzle, freezing, moderate or heavy. 56 Drizzle, freezing, light. WW = 55-50 Use code figures 55-50 to report drizzle (but not freezing drizzle or drizzle mixed with rain) at the station at the time of observation. 55 Drizzle, not freezing, continuous, heavy at time of observation. 54 Drizzle, not freezing, intermittent, heavy at time of observation. 53 Drizzle, not freezing, continuous, moderate at time of observation. 52 Drizzle, not freezing, intermittent, moderate at time of observation. 51 Drizzle, not freezing, continuous, light at time of observation. 50 Drizzle, not freezing, intermittent, light at time of observation. Table 11-6 Coding of Present Weather, WW (Continued)

Code WW

Present Weather

WW = 49-00 Use code figure 49-00 when no precipitation is occurring at the station at the time of observation. = 49-40 Use code figures 49-40 only if there is fog. The fog may be made of water droplets or ice crystals (ice fog). The visibility in fog or ice fog must be less than 5/8 mi. If the visibility is 5/8 mi or more, use code figure 10. The code figure used will depend on whether the fog has changed during the past hour and whether the sky can be seen (blue sky, stars or higher clouds). 49 Fog depositing rime, sky invisible.

Fog that deposits rime will be made up mostly of supercooled water droplets, not ice crystals.

48 Fog, depositing rime, sky visible. 47 Fog or ice fog, sky invisible. Fog has begun or has become thicker during the

preceding hour. 46 Fog or ice fog, sky visible. Fog has begun or has become thicker during the



preceding hour. 45 Fog or ice fog, sky invisible. Fog has shown no appreciable change during the

preceding hour. 44 Fog or ice fog, sky visible. Fog has shown no appreciable change during the

preceding hour. 43 Fog or ice fog, sky invisible. Fog has become thinner during the preceding hour. 42 Fog or ice fog, sky visible. Fog has become thinner during the preceding hour. 41 Fog or ice fog in patches. Fog has begun or has become thicker during the

preceding hour. 40 For or ice fog at a distance at the time of observation, but not at the station

during the preceding hour, the fog or ice fog extending to a level above that of the observer.


Code Present Weather WW = 39-30 Use code figures 39-30 to report a duststorm, sandstorm, or drifting or blowing snow. WW = 39-36 In deciding among code figures 39-36, the following must be considered: snow that is being moved by the wind may be generally low (below about 6 ft) or generally high (above 6 ft). If the snow is low, it is drifting snow; if high, it is blowing snow. Code figure 37 is not reported under United States rules. 39 Heavy blowing snow, generally high (above eye level). Visibility less than 5/16

mi. 38 Light or moderate blowing snow, generally high (above eye level). Visibility 6

mi 36 Drifting snow, generally low (below eye level). WW = 35-30 In deciding among code figures 35-30 the following must be considered: if the visibility at the station at the time of observation is less than 5/16 mi, there is a severe duststorm or sandstorm; if the visibility is at least 5/16 mi but less than 5/8 mi, there is a light or moderate duststorm or sandstorm. The code figure used depends on the intensity of the duststorm or sandstorm and any change in its intensity during the preceding hour. 35 Severe duststorm or sandstorm that has begun or has increased during the

preceding hour. 34 Severe duststorm or sandstorm that has had no appreciable change during the

preceding hour. 33 Severe duststorm or sandstorm that has decreased during the preceding hour. 32 Light or moderate duststorm or sandstorm that has begun or has increase

during the preceding hour. 31 Light or moderate duststorm or sandstorm that has had no appreciable change

during the preceding hour. 30 Light or moderate duststorm or sandstorm that has decreased during the

preceding hour. Table 11-6 Coding of Present Weather, WW (Continued)



11-10

Code Present Weather WW = 29-20 Use code figures 29-20 to report precipitation, fog, ice fog, or thunderstorm at the station during the preceding hour but not at the station at the time of observation. Use code figures 29-25 if the precipitation was showery; otherwise use code figures 24-20. 29 Thunderstorm (with or without precipitation).

Since by U.S. definition, a thunderstorm ends 15 minutes after the last thunder or lightning, the last thunder or lightning must have happened at least 15 minutes before the time of the observation.

28 Fog or ice fog. The visibility in the fog or ice fog must have been less than 5/8 mi.

27 Shower(s) of hail, small hail, or ice pellets, or of rain and hail, small hail, or ice pellets.

26 Shower(s) of snow, or of rain and snow 25 Shower(s) of rain. 24 Freezing drizzle or freezing rain, not falling as shower(s). 23 Rain and snow or ice pellets, not falling as shower(s). 22 Snow not falling as shower(s). 21 Rain (not freezing), not falling as shower(s). 20 Drizzle (not freezing) or snow grains, not falling as shower(s). Table 11-6 Coding of Present Weather, WW (Continued)

Code Present Weather WW = 19-00 Use code figures 19-00 to report certain hydrometeors, electrometeors, lithometeors or no precipitation at the station at the time of observation or during the preceding hour. 19 Funnel cloud(s), tornado, or waterspout at or within sight of the station during

the preceding hour of the time of observation. Since the highest code figure is reported (except code figure 17), code figure 19 cannot be used if WW can be encoded as some higher number.

18 Squalls. By U.S. definition, a sudden increase of at least 15 knots in average wind speed and sustained at 20 knots or more for at least 1 minute. This must occur at or within sight of the station during the preceding hour or at the time of observation. If a squall without any precipitation is observed, either at the time of observation or during the past hour, use code figure 18. If there was any precipitation, or if there was a thunderstorm with the squall, use one of the other code figures, possibly code figure 29 or one of the code figures 99-80. Select the one that best describes what happened.

WW = 17 Thunderstorm, but no precipitation at time of observation. Code figure 17 has priority over code figures 49-20 and 16-00. 17 Thunderstorm, but no precipitation at time of observation.

A thunderstorm is an electrical storm that may or may not be accompanied by precipitation. Since by U.S. definition, a thunderstorm does not end until 15 minutes after the last lightning or thunder, code figure 17 would be used if the thunderstorm occurred within 15 minutes of the observation.



16 Precipitation within sight, reaching the ground or the surface of the sea, near to, but not at the station. The precipitation must be 3 mi or less from the station, but not at the station to use code figure 16.

15 Precipitation within sight, reaching the ground or the surface of the sea, but distant; i.e., estimated to be more than 3 mi from the station.

14 Precipitation within sight, not reaching the ground or the surface of the sea. Sometimes precipitation may fall from a cloud, but into air that is dry enough to evaporate it before it can reach the ground. This is fairly common in desert areas like some parts of the southwestern United States. This phenomenon is called virga.


Code Present Weather 13 Lightning visible, no thunder heard.

There are two reasons you may see lightning but not hear thunder. The first is that the lightning may be far enough away that the thunder doesn't reach the station. The other is that local sounds may muffle the thunder. Use code figure 13 to report distant lightning.

WW = 12-10 Use code figure 12 or 11 to report shallow fog. Continuous refers to covering half or more of the ground or sea; patchy refers to less than one-half coverage. The apparent visibility shall be less than 5/8 mi. Code figure 10 is used to report fog that is neither shallow nor has visibility less than 5/8 mi. (Code figures 49-40 are used to report fog that is not shallow but with visibility less than 5/8 mi.) 12 More or less continuous shallow fog or ice fog at the station; the fog or ice fog is

not deeper than about 6 ft.

11 Patches of shallow fog or ice fog at the station; the fog or ice fog is not deeper than

10 Mist Code figure 10 refers only to water droplets and ice crystals. The visibility restriction shall be 5/8 mi or more but less than 7 mi. Use code figure 10 whether the mist is patchy or more or less continuous.

WW = 09-04 Use code figures 09-04 to report lithometeors. 09 Duststorm or sandstorm within sight at the time of observation, or at the station

during the preceding hour. Visibility in dust or sand must be (or have been) 6 mi or less.

08 Well-developed dust whirl(s) (devils) or sand whirl(s) seen at or near the station during the preceding hour or at the time of observation, but no duststorm or sandstorm.

07 Dust or sand raised by wind at or near the station at the time of observation, but no well-developed dust whirl(s) (devils) or sand whirl(s), and no duststorm or sandstorm seen. Visibility at the time of observation must be 6 mi or less.

06 Widespread dust in suspension in the air, not raised by wind at or near the station at the time of observation.



11-12

This code figure may be used with any visibility, as long as there is dust in the air. Table 11-6 Coding of Present Weather, WW (Continued)

Code Present Weather 05 Haze

Code figure 05 is not restricted to the definition for reports of haze in the basic observation, but can be used if it is simply hazy, regardless of the visibility.

04 Visibility reduced by smoke; e.g., veldt or forest fires, industrial smoke, or volcanic ash. If the smoke is coming from a great distance, it will be spread through a deep layer of the atmosphere. In this case, use code figure 04 regardless of how much the visibility is restricted. If the smoke is coming from somewhere fairly close, then it will be pretty much layered in the lower atmosphere. In this case, the visibility has to be 6 mi or less before code figure 04 is used.

WW = 03-00 Phenomena without significance. 03 Clouds generally forming or developing.

Used only if there are clouds at the time of the observation, no other weather exists, and the clouds have increased or become more developed during the past hour.

02 State of sky on the whole unchanged. This is the characteristic of the sky during the past hour.

01 Clouds generally dissolving or becoming less developed. This is the characteristic of the sky during the past hour. Used if the sky is clear at the time of observation, but there were clouds during the past hour. Also used when clouds have dissolved or become less developed during the past hour.

00 Cloud development not observed or not observable. This is the characteristic of the past hour. Used if clouds were not observed during the past hour, whether the sky is clear or not at time of observation.

11.9 Example of Observations

Sky: 3/8 moderate cumulus at 2100 feet, 1/8 stratocumulus at 5000 feet, 2/8 altocumulus (one level, opaque) at 12000 feet. State of sky generally becoming less developed during past hour. Weather: Light rain shower ended 17 minutes before observation. Code: 485702501 Sky: Clear sky with few patches of semi-transparent altocumulus at 15000 feet. Altocumulus covered 4/8 of sky during past hour. Weather: None. Code: 109300101 Sky: Surface-based obscuration in fog with 300 feet vertical visibility.



Weather: Fog with visibility 1/2 mile. Last hour had a partial obscuration (fog) and 8/8 stratus at 400 feet. Code: 9////4747 Sky: 7/8 cumulonimbus (no anvil visible) at 1800 feet, 1/8 cirrus at 35000 feet, originating from cumulonimbus. Weather: Moderate showers of rain and small hail. Lightning seen in distance (on horizon), but no thunder heard. Code: 734038813 Sky: 8/8 stratocumulus (with breaks) at 4500 feet. State of sky unchanged during the past hour. Weather: None. Code: 756//0202 Sky: 8/8 nimbostratus at 2100 feet. State of sky unchanged during past hour. Weather: Light rain and drizzle. Patchy fog reducing visibility to 3 miles was present during past hour but not at time of observation. No other changes. Code: 8052/5802



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Revision B June 2009 12-1 Communiations and Quick Guide

CHAPTER 12 Communications Architecture & Rawinsonde Quick Guide

12.1 CHUAS Communications Architecture CHUAS are part of the RMTN (Region IV Meteorological Telecommunications Network) portion of the ISCS (International Satellite Communications System). Observations are sent from site via ISCS satellite transceiver to the NWSTG FTP server. http://www.nws.noaa.gov/iscs/contact.htm ISCS support for RMTN is part of a cooperative effort between NWS and WMO to improve the Global Telecommunications System (GTS), in WMO (World Meteorological Organization) Region IV (North and Central America). RMTN allows for a two-way exchange of meteorological information between the United States and nations in the Caribbean and Central America. ISCS uses the INTELSAT 903 satellite to disseminate meteorological products to users over the Atlantic Ocean. ISCS satellite uplinks (ground stations), are located at three Verizon International Gateways. Andover Maine covers the Atlantic Ocean region. Reception of the satellite broadcast is based on the Very Small Aperture Terminal (VSAT) technology, consisting of a 2.4 meter parabolic antenna. Other required hardware at receiving sites includes the radio receiver, satellite modem, and a user workstation to receive and process the satellite broadcast. The observations are then incorporated into the daily collective for broadcast via the ISCS and the GTS. The Aeronautical Fixed Telecommunications Network (AFTN) is successfully used for backup to transmit the upper-air observations to the Global Telecommunications System (GTS).

12.1.1 CHUAS Local Communications Procedures The CHUAS have slightly different procedures for getting the upper-air messages from the IMS-1500C workstation to the Forecast Office or Main Office and then placed onto the COROBOR System and transmitted to the ISCS. Some sites utilize the (EDIS) E-mail Data Ingest System to send Upper Air Messages direct to the National Weather Service Telecommunication Gateway (NWSTG) - also known as the Regional Telecommunication Hub (RTH), via email. The CHUAS local communication procedures are as follows:

1. Bahamas

a. Transmits the upper air observation using the Email Data Ingest System (EDIS). Saved messages in Note Pad are copied to a floppy or memory stick. Another computer in office has Internet Explorer installed and the messages are pasted into the body of an email. The setup account (e-Mail address) for this site is “[email protected]”.

2. Barbados


Communications and Quick Guide June 2009 Revision B

12-2

a. When the messages are ready for transmission, the observer dials up the internet provider and using Outlook Express sends an e-mail to the Forecast (Main) Office. The e-mail has the message attached and also pasted into the new message menu. The Main Office copies the attachment on a 3½ floppy for loading onto the COROBOR System. The pasted message is for local office use.

b. As a backup or normal procedure transmit messages using Internet Explorer.

c. Display the TEMP-1 message (the message is in WordPad)

d. Copy the TEMP-1 message into Notepad

e. Go to Yahoo.com Mail

f. Enter username: [email protected]

g. Enter password: “********” h. Select Compose message and enter the follow information:

1). TO: [email protected] 2). Subject: EDIS MESSAGE INPUT.

i. Paste Temp-1 (163.001.TP1) from Notepad and insert into the body of the message.

Insert four NNNN (CAPITAL LETTERS) after each section, making sure to include a line feed between NNNN and next message part.

j. Repeat the steps “h” and “I” to send message to main office (using main office e-mail address) or others.

3. Belize

a. Belize Upper-air Division is co-located with the Forecast Office and copies the messages to a memory stick or floppy and goes to the COSESNA AFTN terminal to format the message and using the METLab computer for uplink to the ISCS.

b. The Email Data Ingest System (EDIS) is also used as backup communications.

4. Curacao a. Curacao Upper-air division is co-located with the Forecast Office and have slightly

different procedures for getting the upper-air messages from the IMS-1500C workstation and placed onto the COROBOR and/or the METlab System to be transmitted over the ISCS to Washington.

i. The Email Data Ingest System (EDIS) is also used as backup communications.

5. Dominican Republic (Santo Domingo) b. Copies the Message(s) to a floppy and goes upstairs to the forecast office where

they use the AFTN to format the message and using the COROBO System to transmit (up-link) to the ISCS.

c. The Email Data Ingest System (EDIS) is used for backup communications.

6. Grand Cayman

a. Grand Cayman Upper-air Division is co-located with the Forecast Office copies the messages to a memory stick and goes to the AFTN to format the message and using the METLab computer (upper air computer is located within the forecast office) for uplink to the ISCS.



b. On the AFTN click stored 1). Select UM

2). Delete previous message

3). Click edit

4). Insert new message from stick drive

5). Change the message header for TTAA to “UMGC01 MWCG

6). Delete the remaining headers for parts TTBB and PPBB

7). Delete any line feeds between the parts of the message

8). Send

c. On the Metlab

9). In message composer select UM

10). Insert the message into the space provided

11). Delete headers from all parts of the message

12). Preview the message

13). Send

7. Jamaica

a. Transmits the upper air observation using the Email Data Ingest System (EDIS). Saved messages in Note Pad are copied to memory stick. Another computer in office has Internet Explorer installed and the messages are pasted into the body of an email. The setup account (e-Mail address) for this site is “[email protected]”.

b. The AFTN and the COROBOR function as the backup systems for EDIS.

c. The five files (STD, TMP1, TMP2, PYS, and SIG) are copied to another folder for local climatological use.

8. San Andres

a. Originally transmission of messages at San Andres was to send them via FTP or e-Mailed to Met Services in Bogota. The headquarters sends the messages through METLab to Washington. They also print two copies, one for local office archive and the other copy for Civil Aeronautical Authorities (CAA). The CAA digitizes the message and sends it to the headquarters in Bogota via AFTN system. The CAA is not obligated to transmit this kind of message and sometimes it is not sent. This procedure will be maintained for backup of messages.

b. San Andres now transmits the upper air observation messages using the Email Data Ingest System (EDIS). After several attempts to transmit via EDIS, San Andres was successful on Dec 7, 2006 and received confirmation via NCEP QAP. The setup account (e-mail address) for this site is [email protected] with the User Name of: SKSP80001 and Password:xxxx

9. St. Maarten



12-4

a. St Maarten Copies the messages to a floppy and goes to the METlab computer (located with the upper-air office) for uplink to the ISCS. The Email Data Ingest System (EDIS) is used for backup communications.

10. Trinidad a. Once the 100mb is coded into the TTAA, “Create all Reports” to ensure that the

messages are coded properly. A calculation of the Precipitable Water Content is done and the messages either faxed or emailed (using Microsoft Outlook) to the Synoptic Branch. The Synoptic Branch is called to inform them of the transmission and to confirm receipt of same. This information is logged into a log book, detailing the times of receipt or transmission of each part of the sounding.

b. The officers at the Synoptic branch would then be responsible for transmission to the International community via the COROBOR and AFTN systems.

c. At the end of the flight (termination) all reports are again created. The entire sounding is then copied to the pre-formatted form with the P.W.C. The second three messages are sent to the Synoptic branch for transmission.

12.2 NWS Email Data Input System (EDIS)

The NWS Email Data Input System (EDIS) is a procedure that allows designated meteorological data providers the capability to input weather bulletins to the National Weather Service Telecommunication Gateway (NWSTG) - also known as the Regional Telecommunication Hub (RTH), via email.

For detailed information go to Web Page: http://www.weather.gov/tg/emailingest.html This capability requires prior establishment of procedural controls.

See EDIS Access Request Information Form Below

NOTICE: This is an automatic process and every message submission will be disseminated world-wide as determined by the routing established for the WMO abbreviated heading you used. The submitting NMC or organization is responsible for the content of the bulletin(s).

EDIS Access Request Form 1. Name of NMC or sender: Bahamas, Nassau (mynn) 2. From Email Address: “[email protected]”. 3. Name of Contact(s): Leonard Major 4. Phone number(s): (242) 377 7461 5. Name of Shift Observer(s): L. Major, O. Theophilus, and S. Maura 6. Phone Number(s): Same as above 7. Name of Director: Arthur Rolle 8. Phone Number(s): ( 242) 356-3726



EDIS Access Request Form 1. Name of NMC or sender: Barbados, Christchurch (tbpb) 2. From Email Address: [email protected] 3. Name of Contact(s): Victor Estwick (Supervisor) Randolph Roberts (ET) 4. Phone number(s): (246) 428-8767 5. Name of Shift Observer(s): Terry Norse, David Springer, D. Millar, and Dona Millar 6. Phone Number(s): Same as above 7. Name of Director: Chester Layne 8. Phone Number(s): (246) 428 0910

EDIS Access Request Form

1. Name of NMC or sender: Belize, Ladyville (mzbz) 2. From Email Address: [email protected] 3. Name of Contact(s): Albert Jones 4. Phone number(s): [501] 225 2012 [501] 225 2054 5. Name of Shift Observer(s): Stephen Gill (Senior UA Operator), Mervin Kingston, Thomas Wright, Anthony Briceno, and Mr. Gayetano 6. Phone Number(s): Same as above 7. Name of Director: Carlos Fuller 8. Phone Number(s): [501] 225 2012 [501] 225 2054

EDIS Access Request Form 1. Name of NMC or sender: Curacao, N. A. (tncc) 2. From Email Address: [email protected] 3. Name of Contact(s): Hubert Koeyers 4. Phone number(s): [599-9] 839 3367 5. Name of Shift Observer(s): M. Sabina, R. Pereira, R. Apostel, H. Bomberg and A. Pikeur 6. Phone Number(s): Same as above 7. Name of Director: Arthur Dania 8. Phone Number(s): [599-9] 839 3367



12-6

EDIS Access Request Form 1. Name of NMC or sender: Grand Cayman Is. (mwcr) 2. From Email Address: [email protected] 3. Name of Contact(s): John Tibbets 4. Phone number(s): (345) 949 4528 5. Name of Shift Observer(s): Winston Gail, Sharon Ebanks, Gilbert Miller, Floyd Webb, and LiMardo Scott 6. Phone Number(s):

7. Name of Director: Fred Sambula

8. Phone Number(s): (345) 949 4528

EDIS Access Request Form 1. Name of NMC or sender: Dom. Republic, Santo Domingo (mdsd / 78486) 2. From Email Address: [email protected] 3. Name of Contact(s): Gloria Ceballos, Oficina de Meteorologia 4. Phone number(s): (809) 788 1122 x247

5. Name of Shift Observer(s): J. Pool, J. Concepcion, H. Medina, and T. Sequra (ET)

6. Phone Number(s): (809) 788 1122 x247 7. Name of Director: Almando Zorrilla 8. Phone Number(s): (809) 788 1122 x247

EDIS Access Request Form 1. Name of NMC or sender: Jamaica, Kingston (mkjp) 2. From Email Address: [email protected] 3. Name of Contact(s): Charles Reid 4. Phone number(s): (876) 924-8256 5. Name of Shift Observer(s): J Whyte, R. Patterson, and R. Campbell 6. Phone Number(s): (876) 924-8256 7. Name of Director: Sylvia McGill 8. Phone Number(s): (876) 960-8990



EDIS Access Request Form

1. Name of NMC or sender: San Andres Is., Columbia (sksp) 2. From Email Address: [email protected] 3. Name of Contact(s): William Archbold (site supervisor) 4. Phone number(s): [57-8] 512-0257 or 0258 5. Name of Shift Observer(s): 6. Phone Number(s): Same as above 7. Francisco Hidalgo Arias (Columbia Main Office) supervisor of all (5) upper-air sites 8. Phone Number(s): [57] (1) 266-2115

EDIS Access Request Form 1. Name of NMC or sender: St. Maarten, N. A. (tncm) 2. From Email Address: [email protected] 3. Name of Contact(s): Rignald Eugenio Chief Observer 1st Class A “Acting chief Met. Office” 4. Phone number(s): [599] 545-2024 5. Name of Shift Observer(s): A. Bary, C. Brill, S. Powell, and E. Martiena 6. Phone Number(s): Same as above 7. Name of Director: Arthur Dania 8. Phone Number(s): [ 599-9] 839-3367

EDIS Access Request Form 1. Name of NMC or sender: Trinidad, Piarco (ttpp) 2. From Email Address: [email protected] 3. Name of Contact(s): Arlene Aaron 4. Phone number(s): 868 669 5465 5. Name of Shift Observer(s): Deryck Dhanie, Kiran Sedoo, Rachael Ramnath 6. Phone Number(s): 868 669 5465 7. Name of Acting Director: Emmanuel Moolchan 8. Phone Number(s): 868 669 5465



12-8

12.2.1 Guidance for using EDIS A. General Rules

1. All input is ALPHANUMERIC ONLY.

2. The email is submitted to the RTH via EDIS using a predefined email address. B. Procedures for Copying Messages into Body of Email

1. If TEMP message is in WordPad on iMetOS

2. Copy Message into Notepad.

3. Leave the separator (=) signal immediately after last text for each message (TTAA, TTBB, PPDD) without spaces (see Temp Figures below)

4. Each message must be ended with “NNNN” CAPITAL LETTERS (TTAA, TTBB, PPDD) on next line after the separator (=) signal. (see Temp Figures below)

5. Ensure there is one line feed between each part of Temp messages. (see Temp Figures below)

6. Copy TEMP message and save to memory stick or floppy

C. EDIS Submission Rules and Definitions

1. The e-mail is submitted to the RTH via EDIS using a predefined e-mail address (i.e., [email protected]) Go to Yahoo.com Click on Mail Enter yahoo ID: [email protected] Enter Password “*********” Sign in

2. Messages are sent to the following address: [email protected]

3. The "subject line" shall contain: EDIS Message Input

4. Paste Messages from (Notepad only) in the body of email. (See Figures Below)

5. Ensure Temp message has been copied into body of e-mail correctly (i.e., making sure the “NNNN” are on next line after the separator (=) signal).

6. Send Message



Figure 12-1: Temp-1

Figure 12-2: Temp-2



12-10

12.3 Transmission of Upper Air Archive Data to NCDC The Archived Files may be sent to NCDC only via FTP. The e-mail of archived flights has been discontinued and CHUAS are encouraged to send archived flights via FTP. E-mail procedures are inserted here for information only until all CHUAS are sending archived data via FTP (see section 12.3.2).

12.3.1 E-Mail Archived Data to NCDC This information contains step-by-step instructions on how to compress Upper Air data files and to email the “zipped” data to the NCDC.

You may use any program that creates a compressed data “.zip” file. The site manager should obtain a legal version of WinZip or ALZIP and install on the SMC. You can download ALZip free from here: http://www.download.com/3001-2250_4-10631836.html?idl=n.

12.3.1.1 Creating the Upper Air Data file

The iMetOS automatically archives the NWS files (.HDR, .DAT, and .HRS) to the designated directory (c:\upperair\2008\may). The directory Year and Month are changed automatically in iMetOS. DO NOT MAKE THIS DIRECTORY

1. The iMetOS places the three (3) NWS files into “c:\upperair\2008\may” unzipped.

2. The Ingest and QC programs at NCDC read certain data from certain columns in the NWS files. If you increase (or decrease) the length of the data, the columns will be out of alignment and the data is unusable.

3. The Observer must “NOT” insert any other data in the ascension number (file name) in the “New Sonde Parameters File”. Just enter the ascension number (three digit number).

4. At the end of the month open the C:\upperair\2008\may (or current year/month) sub directory

5. The files in the monthly folder should be H, T, or R followed by Ascent Number. (Example # 001 – files would be: H001, T001, and R001)

a. H001-H062 [NWS Identification Record (.HDR)] H001-H031if one launch per day

b. T001-T062 [NWS Data Record (.DAT)] T001-T031 if one launch per day

c. R001-R062 [NWS High Resolution Record (.HRS)] R001-R031 if one launch per day

6. You must check and verify the ascension numbers and dates. The folder should contain data for the current month only.

7. Now select all files in folder (ctrl-A).

8. Right-click on files and select “add to ZIP”

a. Do not right-click on the folder and “add to zip” as this will include the folder name on your PC as the path name when it extracts and your data will not be processed.

b. Make sure that the “save full path info” is not checked under the Folder Option. NOTE: If this is checked it will create a separate sub-folder and your data will not be processed.



9. Right click on mouse and select the WinZip - Add to aug (or current month). A ZIP folder will appear within the aug (or current month) folder

10. Rename the Zip folder (xxxxmmyy) mkjp0508: Name the zip folder according to the rules below: WHERE:

o xxxx is the 4-letter call sign for station, mm is the 2-digit data month (01-12) , yy is the last 2 digits of the data year (01-99) Example: mkjp0508.zip (for may of 2008) NOTE: the .zip will be automatically

added.

11. Close the ZIP program.

12. Open your e-mail program and log in.

13. To send monthly archives to NCDC, follow the procedures in 12.3.2

12.3.1.2 CHUAS WMO Station Number, ICAO Call Sign, and WBAN ID

Table 12-1: Station Number & Call Sign

Station Name WMO Station Number ICAO Call Sign WBAN ID A1A2 Bahamas 78073 mynn 12717 BA Barbados 78954 tbpb 11501 BR Belize 78583 mzbz 11818 BH Curacao 78988 tncc 11643 NU Dom. Republic 78486 mdsd 11629 DR Grand Cayman 78384 mwcg 11813 GC Jamaica 78397 mkjp 11715 JM San Andres 80001 sksp 11814 CO St. Maarten 78866 tncm 11645 MN Trinidad 78970 ttpp 11634 TD

12.3.2 FTP Archive Data to NCDC This information contains step-by-step instructions on how to compress Upper Air data files and to FTP the “zipped” data to the NCDC.

You may use any program that creates a compressed data “.zip” file. The site manager should obtain a legal version of WinZip or ALZIP and install on the SMC. You can download ALZip free from here: http://www.download.com/3001-2250_4-10631836.html?idl=n

12.3.2.1 Creating the Upper Air Data file

The iMetOS automatically archives the NWS files (.HDR, .DAT, and .HRS) to the designated directory (c:\upperair\2008\dec). The directory Year and Month are changed automatically in iMetOS. DO NOT MAKE THIS DIRECTORY

1. The iMetOS places the three (3) NWS files into “c:\upperair\2008\dec” unzipped.

2. The Ingest and QC programs at NCDC read certain data from certain columns in the NWS files. If you increase (or decrease) the length of the data, the columns will be out of alignment and the data is unusable.

3. The Observer must “NOT” insert any other data in the ascension number (file name) in the “New Sonde Parameters File”. Just enter the ascension number (three digit number).



12-12

4. At the end of the month open the C:\upperair\2008\dec (or current year/month) sub directive

5. The files in the monthly folder should be H, T, or R followed by Ascent Number. (Example # 001 – files would be: H001, T001, and R001)

a. H001-H062 [NWS Identification Record (.HDR)] H001-H031if one launch per day

b. T001-T062 [NWS Data Record (.DAT)] T001-T031 if one launch per day

c. R001-R062 [NWS High Resolution Record (.HRS)] R001-R031 if one launch per day



8. Right-click on files and select “add to ZIP” or send to compressed folder.



9. The Add Menu appears with the following path (c:\upperair\2008\dec\

10. Type mkjp1208 (xxxxmmyy) to name the zip folder according to the rules below: WHERE:

o xxxx is the 4-letter call sign for station, mm is the 2-digit data month (01-12) , yy is the last 2 digits of the data year (01-99) Example: mkjp1208.zip

11. Close the ZIP program

12.3.2.2 FTP the Data File to NCDC

1. Send the archive folder via FTP file to NCDC.

a. Open Windows Explorer by using the following keys [Windows Key + E].

1) In address bar, type ftp://ftp.ncdc.noaa.gov/pub/upload.

2) This will place NCDC’s FTP site on the directory tree on the left.

3) Navigate to folder or drive with archive data (mkjp0508.zip).

4) Right-click the zip file created in above section and select “copy”.

5) Right-click the folder named: Internet Explorer – ftp.ncdc.noaa.gov/pub/upload

6) The space on the right will be blank. Right-click that blank space and select “paste”.

7) The file name will appear on the right hand side if you are successful.

8) At this time, the file has been sent and you are done.

12.3.2.3 Storing Archived Files

It is recommended that since these files are so small, that they be kept indefinitely in



(c:\upperair\1008\dec), or current month/year in case they are needed to be resent.

12.4 CHUAS IMS-1500 Quick Guide for Rawinsonde Flights The Quick Guide for Rawinsonde Flights will be revised and/or prepared at training session with each upper-air station manager.

12.4.1 Bahamas Quick Guide for Rawinsonde Flights

1. Inflate balloon 45 minutes before release. During fair weather conditions, optimum performance will routinely be achieved with free lift ranging from 1000 to 1300 grams. The standard, average ascension rate should be 300 meters per minute. Adjust the free lift until this average is obtained.

2. Remove the balloon from the nozzle. Secure the balloon inside the inflation shelter by tying it to a hook or the measuring weights.

3. Attached (unwinder, parachute, and light). If regulator is not used the train cord shall be at least 25 meters.


4. Turn on the UPS (if not already on) and the power strip to activate the SPS.

5. Turn on the computer (upper air workstation)

6. Remove a radiosonde from the box and packaging.

7. Open the can for the hygristor and place the hygristor it its place in the radiosonde.

8. Power the radiosonde with the power supply or battery (preferred) after the following steps:

a. Prepare the radiosonde battery for exactly 2 minutes in water.

b. Shake the water out of the radiosonde battery and enclose in plastic bag.

c. Connect the B-2 battery to the voltage check until the proper 17.5 volts is reached.

d. Connect battery to Radiosonde



12-14

9. Open the iMetOS software in “Real Flight” mode

10. Point the antenna in the general direction where the radiosonde will be baselined (AZ= 250 EL= 0) NOTE: The tracking Mode must be “OFF” Then left double click in the black area of the azimuth and/or elevation. The antenna will respond rapidly.

11. With the AFC Off, Push the “Frequency Search” button to search for the radiosonde.

12. To initialize the flight data record, select New from the File menu on the Flight Screen menu bar, or from the Flight Screen toolbar. The SPS should be on and receiving data to activated the NEW menu.

13. Sonde Parameters appears



14. Hit the “…..” button and load the B2 calibration file from the C:\IMS\iMetOS\B2 directory.

Note: Select (CSR) if radiosonde is “RECON” or (CSN) if radiosonde is “NEW” from the dropdown “Files of type” and click “OPEN”.

15. The Sonde Parameters Screen re-appears with the Sonde ID and the Calibration File Name filled in with the calibration file name. “Click OK”

16. Preflight Screen appears with Sonde ID inserted



12-16

17. Enter the preflight data as listed below and click “OK”

a. Pressure – Station pressure shall be taken from the PDB to the nearest tenth of a Hectopascal (hPa).

b. Temperature – Record the dry bulb temperature to the nearest tenth of a degree Celsius

c. Humidity – Record the humidity to the nearest tenth of a percent

d. Wind Direction – Enter to the nearest tenth of a degree. For calm winds, estimate a direction or use 360 degrees.

e. Wind Speed – Enter to the nearest tenth of a knot. For calm winds, a single “0” can be entered for wind speed.

f. Cloud Code – Enter the five digit code NhCLhCMCH

g. Weather (WX) Code – Enter the four digit code WWWW (Two groups of Present Weather with the first two digits used for the highest priority, see Chapter 11).

h. See Note and then click Save



NOTE: Do not press the Save button on the Preflight Data Entry screen until the Radiosonde Status Check has been completed and rechecked. The Preflight Data can not be changed after the release.

18. With the iMetOS, turn off “AFC” and do a “Frequency Search” for the Radiosonde.

19. Wait for at least 60 data records. If the record numbers do not increase, move either the Radiosonde, and/or the antenna 5-10 degrees in azimuth and/or elevation. Return the Tracking Mode to Off

20. Take the Radiosonde to the inflation room and tie it to the balloon. Allow the Radiosonde to become acclimated to the environment before releasing.

NOTE: The sonde must not be placed on the ground at any time! This can cause antenna loading which will cause a frequency shift once it’s released.

21. If the antenna was moved or if it was not already done, point the antenna in the general direction where the Radiosonde will go when launched. Ensure the Tracking Mode to Off.

22. Call the Control Tower to get approval for the release if required.

23. Launch the radiosonde.

24. Turn on Automatic Tracking by hitting the “4” button on the CDU or from the workstation, place the Tracking Mode to ON.

25. It is vital that the frequency and signal strength be checked prior to and immediately after the release. This should be done using the CDU at the release site.

26. iMetOS is designed to recognize the 4mb change in pressure that indicates the start of flight.

27. Move the antenna as necessary with the CDU to reduce the tracking errors to an absolute value less than 150 or from workstation (tracking off) “double click inside the black area to position required. If the errors do not settle to less than 20, turn off Automatic Tracking and move the antenna to the radiosonde. Turn on Automatic Tracking. Repeat as necessary.

28. Make sure the IMS-1500C equipment is not tracking a "side lobe". If it is determined side lobe tracking is occurring, set the tracking mode to Manual. Gradually adjust the elevation and azimuth angles (7 degrees on each side) until a significant increase in signal strength occurs. Reset the tracking mode to Auto Tracking.

29. When the Temp-1 report is generated and ready for transmission, check times in the Abbreviated Header and in coded data.

30. It may be necessary to correct or edit the coded messages prior to transmission.

31. The NWS Email Data Input System (EDIS) is a procedure that allows designated meteorological data providers the capability to input weather bulletins to the National Weather Service Telecommunication Gateway (NWSTG) - also known as the Regional Telecommunication Hub (RTH), via email using the following procedures:

a. Procedures for Copying Messages into Body of Email

1) TEMP message is in WordPad on iMetOS

2) Copy Message into Notepad.



12-18

3) Leave the separator (=) signal immediately after last text for each message (TTAA, TTBB, PPDD) without spaces (see Temp Figures below)

4) Each message must be ended with “NNNN” CAPITAL LETTERS (TTAA, TTBB, PPDD) on next line after the separator (=) signal. (see Temp Figures below)

5) Ensure there is one line feed between each part of Temp messages. (see Temp Figures below)

b. EDIS Submission

1). The e-mail is submitted to the RTH via EDIS using a predefined e-mail address (i.e.,)

2). Go to

3). webmail

4). Enter:

5). Enter Password

6). Compose message

7). Messages are sent to the following address: [email protected]

8). The "subject line" shall contain: EDIS Message Input

9). Paste Messages from (Notepad only) in the body of email. (See Figures Below)

10). Ensure Temp message has been copied into body of e-mail correctly (i.e., making sure the “NNNN” are on next line after the separator (=) signal).

11). Send Message



Temp-1

Temp-2

32. At H+45 (12:45) check the THANKS (Favorites – Upper Air- Quality Assessment Project) for “THKS”. If not available by H+1:00, resend messages.

33. At balloon burst (or end of flight), select “YES” to terminate the flight.

34. Send the Temp-2 report using same procedures as Temp-1



12-20

35. Archive the flight

NOTE: The iMetOS will automatically archive the NWS files (.HDR, .DAT, and .HRS) to the designated directory (c:\upperair\2008\dec). The directory Year and Month is changed automatically in iMetOS. ”DO NOT MAKE THIS DIRECTORY” The NWS files will be sent to NCDC at end of the month via FTP ONLY

36. Archiving allows the user to store IMetOS generated files in a single, compressed file. Archive the flight as follows:


b. Change the “To” directory to C:\IMS\iMetOS\Archives. See Figure below.

c. Double click on [..]: (c:\ims\imetos)

d. Double click on archives: (c:\ims\imetos\archive)

e. Change the “From” directory to C:\IMS\iMetOS\Flights.

f. Select the flight file name in the “File Name” box (flight ascension number). NOTE: If you double click the ascension number the flight will archive to the “TO” directory.

g. Or Click “Archive”.

h. Click “Cancel” after the Command Prompt window automatically closes.

37. Go to File and Exit the iMetOS

38. Shut down the computer.

39. Turn off the power strip to the SPS and UPS.



Sending End of Month Archive Data to NCDC 1. The iMetOS v4.0.0 or later will automatically archive the NWS files to the designated

directory (c:\upperair\2008\dec) unzipped. The directory Year and Month are changed automatically in iMetOS. DO NOT MAKE THIS DIRECTORY

2. At the end of the month open the C:\upperair\2008\dec (or current year/month) sub directive.

3. The files in the monthly folder should be H, T, or R followed by Ascent Number (i.e., Flight 301 would be: H301, T301, and R301)

4. You must check and verify the ascension numbers and dates. The folder should contain data for the current month only. Ensure the file extensions have been removed.






8. Type (xxxxmmyy) to name the zip folder according to the rules below: WHERE: o xxxx is the 4-letter call sign for station, mm is the 2-digit data month (01-12) , yy is

the last 2 digits of the data year (01-99) Example: mynn1208

9. Close the ZIP program FTP the Data File to NCDC

1. Open Windows Explorer by using the following keys [Windows Key + E].

2. In address bar, type ftp.ncdc.noaa.gov/pub/upload. Select GO

3. This will place NCDC’s FTP site on the directory tree on the left.

4. Navigate to folder or drive with archive data (mwcg1208.zip).

a. Right-click the zip file created in above section and select “copy”.

b. Right-click the folder named: Internet Explorer – ftp.ncdc.noaa.gov/pub/upload

c. The space on the right will be blank. Right-click that blank space and select “paste”.

d. The file name will appear on the right hand side if you are successful.

e. At this time, the file has been sent and you are done.



12-22

12.4.2 Barbados Quick Guide for Rawinsonde Flights



3. Attached (regulator, parachute, and light). If regulator is not used the train cord shall be at least 25 meters.


4. Turn on the UPS (if not already on) and the power strip if available to activate the SPS.

5. Turn on the computer (upper air workstation).





b. Shake the water out of the radiosonde battery and enclose in either plastic tube or bag.


d. Connect battery to radiosonde.


10. Point the antenna in the general direction where the Radiosonde will be baselined (AZ= 270 EL= 0) NOTE: The tracking Mode must be “OFF” Then left “double click” in the black area of the azimuth and/or elevation. The antenna will respond rapidly.



11. With the AFC Off, Push the “Frequency Search” button to search for the Radiosonde.

12. To initialize the flight data record, select New from the File menu on the Flight Screen menu bar, or from the Flight Screen toolbar. The SPS must be on and receiving data to activated the NEW menu.





12-24



16. Preflight Screen appears with Sonde ID inserted







d. Wind Direction – Enter to the nearest tenth of a degree. For calm winds, estimate a direction or use 360 degrees

e. Wind Speed – Enter to the nearest tenth of a knot. For calm winds, a single “0” can be entered for wind speed



h. See Note and then click Save.


18. With the iMetOS, turn off “AFC” and do a “Frequency Search” for the Radiosonde

19. Wait for at least 60 data records. If the record numbers do not increase, move either the Radiosonde or the antenna 5-10 degrees in azimuth and/or elevation (step 10). Return the Tracking Mode to OFF.



21. If the antenna was moved or if it was not already done, point the antenna in the general direction where the Radiosonde will go when launched. Ensure the Tracking Mode is off.


23. Launch the Radiosonde.




27. Move the antenna as necessary with the CDU to reduce the tracking errors to an absolute value less than 150 or from the workstation (tracking off) “double click inside the b;ack area to position as required. If the errors do not settle to less than 20, turn off Automatic Tracking and move the antenna to the Radiosonde. Turn on Automatic tracking. Repeat as necessary.



12-26




31. Temp-1 is in WordPad on iMetOS

32. Copy message into Notepad

33. Using Outlook Express with new message menu (subject upper air) Attach first transmission and send to Main Office. They copy from e-mail onto a 31/2 floppy for loading on the COROBOR and transmiting to ISCS

34. Call Main Office and notify them of Temp-1 message.



1) Display TEMP-1 message (if the message is in WordPad)



4) Each message must be ended with “NNNN” CAPITAL LETTERS (TTAA, TTBB, PPDD) on next line after the separator (=) signal. (See Temp Figures below).


b. EDIS Submission

1) The e-mail is submitted to the RTH via EDIS using a predefined e-mail address (i.e.,)

2) Go to Yahoo.com Mail

3) Enter usename [email protected]

4) Enter password “********”

5) Compose message

6) Messages are sent to the following address: [email protected]

7) The "subject line" shall contain: EDIS Message Input 8) Paste Messages from (Notepad only) in the body of email. (See Figures Below)

9) Ensure Temp message has been copied into body of e-mail correctly (i.e., making sure the “NNNN” are on next line after the separator (=) signal).

10) Send Message



Temp-1

Temp-2

36. At H+45 (12:45) check the THANKS (Favorites – Upper Air- Quality Assessment Project) for

“THKS”. If not available by H+1:00, resend messages.

37. At balloon burst (or end of flight), select “Yes” to terminate the flight.

38. Send the Temp-2 report using same procedures as Temp-1.

39. Archive the flight.



12-28



a. From the iMetOS menu bar, go to Utilities | Store Files

b. Change the “To” directory to C:\IMS\iMetOS\Archives (See Figure below)

1) Double click on [..]: directory goes to (c:\ims\imetos)

2) Double click on archives: directory goes to (c:\ims\imetos\archive)

c. Change the “From” directory to C:\IMS\iMetOS\Flights.

d. Select the flight file name in the “File Name” box (flight ascension number). NOTE: If you double click the ascension number the flight will archive to the “TO” directory or click Archive button.

e. Click “Cancel” after the Command Prompt window automatical



43. Turn off the UPS (if directed) and the power strip














the last 2 digits of the data year (01-99) Example: tbpb1208.zip





4. Navigate to folder or drive with archive data (tbpb1208.zip).








12-30

12.4.3 Belize Quick Guide for Rawinsonde Flights






5. Turn on the computer (upper workstation).



8. Power the radiosonde with the power supply oe Bttery (preferred) after the following steps:

a. Prepare the radiosonde battery for exactly 2 minutes in water. b. Shake the water out of the Radiosonde battery and enclose in plastic bag.


d. Connect battery to radiosonde


10. Point the antenna in the general direction where the radiosonde will be baselined (AZ= 270 EL= 0) NOTE: The tracking Mode must be “OFF” Then click in the black area of the azimuth and/or elevation. The antenna will respond instantly.



12-32



16. Preflight Screen appears with Sonde ID inserted.




a. Pressure – Station pressure shall be taken to the nearest tenth of a Hectopascal (hPa), and corrected for the Release Point Pressure by adding “.6”







h. See Note and then click Save.


18. With the iMetOS, turn off “AFC” and do a “Frequency Search” for the Radiosonde

19. Wait for at least 60 data records. If the record numbers do not increase, move either the Radiosonde, or the antenna 5-10 degrees in azimuth and/or elevation. Return the Tracking Mode to OFF



21. If the antenna was moved or if it was not already done, point the antenna in the general direction where the Radiosonde will go when launched. Ensure the Tracking Mode is Off.

22. Call he Control Tower to get approval for the release if required.


24. Turn on Automatic Tracking by hitting the “4” button on the CDU or from the workstation, place the Tracking mode to ON.

25. It is vital that the frequency and signal strength be checked prior to and immedistely after the release. This should be done using the CDU at the release site.


27. Move the antenna as necessary with the CDU to reduce the tracking errors to an absolute value less than 150 or from the workstation (tracking off) “double click inside the black area to position as required. If the errors do not settle to less than 20, turn off Automatic Tracking and move the antenna to the Radiosonde. Turn on Automatic Tracking. Repeat as necessary.



12-34


29. When the Temp-1 report is generated and ready for transmission, check times in the Abbreviated Header and in coded data. It may be necessary to correct or edit the coded message prior to transmission.

30. Transmit message on METLAB (priority) and COSESNA AFTN terminal. If message is copied on METLAB, ensure you copy message onto Notepad before copying onto METLAB

31. The NWS Email Data Input System (EDIS) is a procedure that slows designated meteorological data providers the capability to input weather bulletins to the NWS Telecommunications Gateway (NWSTG) – also known as the Regional Telecommunications Hub (RTH), via email using the following procedures;

a. Display the TEMP-1 message (the message is in WordPad)

b. Copy message into Notepad

1) Leave the separator (=) signal immediately after the last text for each message (TTAA, TTBB, PPDD) without spaces (see Temp Figures below)

2) Each message must be ended with “NNNN” CAPITAL LETTERS (TTAA, TTBB, AND PPDD) on next line after the separator (=) signal. (See Temp Figures below)

3) Ensure there is one line feed between each part of Temp message. (See Temp Figures below).

c. Left-click on File>Save As and change the file name to TEMP-1 099 (ASC Number)

d. Save In (Send the file to the) 3 ½ disk in drive “a”

32. Remove disk “a” drive and place in computer with “Internet explorer”

33. Go to http://mail.hydromet.gov.bz:81/

a. Enter username: [email protected]

b. And password: lex12a

34. Select Compose message and enter the follow information:

a. TO: [email protected]

b. Subject: EDIS MESSAGE INPUT.

35. Open file on 3 ½ disk (TEMP-1 099)



Temp-1

Temp-2



12-36

36. Copy the TEMP-1 message and paste from (Notepad only) insert into the body of the message. Ensure Temp message has been copied into body of e-mail correctly (i.e., making sure “NNNN” are on next line after the separator (=) signal.

37. Send e-mail Message.

38. At H+45 (12:45) check the THANKS (Favirites – Upper Air – Quality Assessment Project) for “THKS”. If not available by K+1:00, resend message.

39. At balloon burst (or end of flight), select “YES” to terminate the flight if screen appears. When setup/system parameters-1, Terminate Flight Automatically is checked, you will not receive this screen, but TEMP-2 message will automatically appear on screen.

a) Check times on TEMP-2 and print messages.

b) Send the Temp-2 report (same procedures as Temp-1).


NOTE: The iMetOS will automatically archive the NWS files (.HDR, .DAT, and .HRS) to the designated directive (c:\upperair\2008\dec). The directive Year and Month is changed automatically in iMetOS. ”DO NOT MAKE THIS DIRECTORY” The NWS files at end of month will be sent to the NCDC via FTP ONLY







f. Select the flight file name in the “File Name” box (flight ascension number). NOTE: If you double click the ascension number the flight will archive to the “TO” directive.







44. Turn off the UPS and the power strip.



12-38












the last 2 digits of the data year (01-99) Example: mzbz1208.zip





4. Navigate to folder or drive with archive data (mzbz1208.zip).








12-40

12.4.4 Curacao Quick Guide for Rawinsonde Flights 1. Inflate balloon 45 minutes before release. During fair weather conditions, optimum

performance will routinely be achieved with free lift ranging from 1000 to 1300 grams. The standard, average ascension rate should be 300 meters per minute. Adjust the free lift until this average is obtained.






6. Remove a Radiosonde from the box and packaging.





c. Connect the B-2 batteey to the voltage heck untilthe proper 17.5 volts is reached.



10. Point the antenna in the general direction where the Radiosonde will be baselined (AZ= 270 EL= 0) NOTE: The tracking Mode must be “OFF” Then left double click in the black area of the azimuth and/or elevation. The antenna will respond rapidly.



12-42







b. Pressure – Station pressure shall be taken from the PDB to the nearest tenth of a Hectopascal (hPa).








18. With the iMetOS, “Turn off “AFC” and do a “Frequency Search” for the Radiosonde.

19. Wait for at least 60 data records. If the record numbers do not increase, move either the Radiosonde, or the antenna 5-10 degrees in azimuth and/or elevation. Return or leave the tracking Mode to Off



21. If the antenna was moved or if it was not already done, point the antenna in the general direction where the Radiosonde will go when launched. Ensue the Tracking Mode is Off.



24. Turn on Automatic tracking by hitting the “4” button on the CDU or from the workstation,



27. Move the antenna as necessary with the CDU (or workstation computer) to reduce the tracking errors to an absolute value less than 150. Turn on Automatic Tracking by hitting the “4” button on the CDU or from the workstation “double click inside the black area to position required. If the errors do not settle to less than 20, turn off Automatic Tracking and move the antenna to the Radiosonde. Turn on Automatic Tracking. Repeat as necessary.

28. Make sure the IMS-1500C equipment is not tracking a "side lobe". If it is determined side



12-44

lobe tracking is occurring, set the tracking mode to Manual. Gradually adjust the elevation and azimuth angles (7 degrees on each side) until a significant increase in signal strength occurs. Reset the tracking mode to Auto Tracking.


30. It may be necessary to correct or edit the coded message prior to transmission.

31. Temp messages are in WordPad on iMetOS, copy messages onto Notepad,.

32. Ccopy the message to a memory stick and go to the AFTN to format the message and using the METlab computer for uplink to the ISCS.

a. On the AFTN click stored

1) Select UM

2) Delete previous message

3) Click edit

4) Insert new message from stick drive

5) Change the message header for TTAA to “UMNU01 TNCC

6) Delete the remaining headers for parts TTBB and PPBB

7) Delete any line feeds between the parts of the message

8) Send

b. On the Metlab

1) In message composer select UM

2) Insert the message into the space provided

3) Delete headers from all parts of the message

4) Preview the message

5) Send



1). If TEMP message is in WordPad on iMetOS

2). Copy Message into Notepad.

3). Leave the separator (=) signal immediately after last text for each message (TTAA, TTBB, PPDD) without spaces (see Temp Figures below)

4). Each message must be ended with “NNNN” CAPITAL LETTERS (TTAA, TTBB, PPDD) on next line after the separator (=) signal. (see Temp Figures below)

5). Ensure there is one line feed between each part of Temp messages. (see Temp Figures below)

6). Copy TEMP message and save to memory stick or floppy



b. EDIS Submission

1). The e-mail is submitted to the RTH via EDIS using a predefined e-mail address

2). Go to Yahoo.com

3). Click on Mail

4). Enter yahoo ID

5). Enter “Password “

6). Messages are sent to the following address: [email protected]

7). The "subject line" shall contain: EDIS Message Input 8). Paste Messages from (Notepad only) in the body of email. (See Figures Below)

9). Ensure Temp message has been copied into body of e-mail correctly (i.e., making sure the “NNNN” are on next line after the separator (=) signal).

10). Send Message

Temp-1



12-46

Temp-2





NOTE: The iMetOS will automatically archive the NWS files (.HDR, .DAT, and .HRS) to the designated directory (c:\upperair\2008\dec). The directory Year and Month is changed automatically in iMetOS. ”DO NOT MAKE THIS DIRECTORY” The NWS archived files will be sent to NCDC at the end of each month via FTP

38. Archiving allows the user to store IMetOS flight files in a single, compressed file. Archive the flight as follows:



1). Double click on [..]: (c:\ims\imetos)

2). Double click on archives: (c:\ims\imetos\archive)


d. Select the flight file name in the “File Name” box (flight ascension number). NOTE: If you double click the ascension number the flight will archive to the “TO” directory.


f. Click “Cancel” after the Command Prompt window automatically closes



12-48

Sending End of Month Archive Data to NCDC

1. The iMetOS v4.0.0 or later will automatically archive the NWS files to the designated directory (c:\upperair\2008\dec) unzipped. The directory Year and Month are changed automatically in iMetOS. DO NOT MAKE THIS DIRECTORY








7. The Add Menu appears with the following path (c:\upperair\2008\aug\


the last 2 digits of the data year (01-99) Example: tncc1208.zip




FTP the Data File to NCDC




4. Navigate to folder or drive with archive data (tncc1208.zip).








12-50

12.4.5 Dominican Republic Quick Guide for Rawinsonde Flights


















12-52



16. Preflight Screen appears with Sobde ID inserted.













19. Wait for at least 60 data records. If the record numbers do not increase, move either the Radiosonde, or the antenna 5-10 degrees in azimuth and/or elevation. Return the Tracking Mode to Off.



21. If the antenna was moved or if it was not already done, Turn Tracking Mode ON and point the antenna in the general direction where the Radiosonde will go when launched and Turn Tracking Mode Off.



24. Turn on Automatic Tracking by hitting the “4” button on the CDU or from the workstation, place the Tracking Mode to ON

25. It is vital the frequency and signal strength be checked prior to and immediately after the release. This should be done using the CDU at the release site.





12-54


29. When the Temp-1 report is generated and ready for transmission, check times in the Abbreviated Header and in coded data. It may be necessary to correct or edit the coded messages prior to transmission.

30. Temp messages are in WordPad on iMetOS, they must be copied into Notepad.

31. Copy the message to a memory stick and go to the AFTN to format the message and using the METlab computer for uplink to the ISCS.

32. The NWS Email Data Input System (EDIS) is a procedure that allows designated meteorological data providers the capability to input weather bulletins to the National Weather Service Telecommunication Gateway (NWSTG) - also known as the Regional Telecommunication Hub (RTH), via email using the following procedures: a. Procedures for Copying Messages into Body of Email

1) If TEMP message is in WordPad on iMetOS





b. EDIS Submission

1). The e-mail is submitted to the RTH via EDIS using a predefined e-mail address

2). Go to Yahoo.com

3). Click on Mail

4). Enter yahoo ID:

5). Enter Password

6). Messages are sent to the following address:[email protected]

7). The "subject line" shall contain: EDIS Message Input 8). Paste Messages from (Notepad only) in the body of email. (See Figures Below)

9). Ensure Temp message has been copied into body of e-mail correctly (i.e., making ure the “NNNN” are on next line after the separator (=) signal).

10). Send Message



Temp-1

Temp-2




12-56




NOTE: The iMetOS will automatically archive the NWS files (.HDR, .DAT, and .HRS) to the designated directory (c:\upperair\2008\dec). The directory Year and Month is changed automatically in iMetOS. ”DO NOT MAKE THIS DIRECTORY” The NWS files will be sent to NCDC at the end of each month via FTP ONLY












12-58











8. Type mdsd1208 (xxxxmmyy) to name the zip folder according to the rules below: WHERE:

o xxxx is the 4-letter call sign for station, mm is the 2-digit data month (01-12) , yy is the last 2 digits of the data year (01-99) Example: mdsd1208.zip





4. Navigate to folder or drive with archive data (mdsd1208.zip).

5. Right-click the zip file created in above section and select “copy”.

6. Right-click the folder named: Internet Explorer – ftp.ncdc.noaa.gov/pub/upload

7. The space on the right will be blank. Right-click that blank space and select “paste”.

8. The file name will appear on the right hand side if you are successful.

9. At this time, the file has been sent and you are done.



12.4.6 Grand Cayman Quick Guide for Rawinsonde Flights












c. Connect the B-2 battery to the viltage check until the proper 17.5 volts is reached.

d. Connect th the radiosonde.





12-60







12-62










18. With the iMetOS, turn off “AFC” and do a “Frequency “Search” for the Radiosonde.

19. Wait for at least 60 data records. If the record numbers do not increase, move either the Radiosonde, or the antenna 5-10 degrees in azimuth and/or elevation.






24. Turn on Automatic Tracking by hitting “4” button on the CDU or from the workstation, place the tracking Mode to ON.




28. Make sure the IMS-1500C equipment is not tracking a "side lobe". If it is determined side lobe tracking is occurring, set the tracking mode to Manual. Gradually adjust the elevation



and azimuth angles (7 degrees on each side) until a significant increase in signal strength occurs. Reset the tracking mode to Auto Tracking.



31. Temp messages are in WordPad on iMetOS, they must be copied into Notepad.

32. Copy the message to a memory stick and go to the AFTN to format the message and using the METlab computer for uplink to the ISCS.

a. On the AFTN click stored

1) Select UM

2) Delete previous message

3) Click edit

4) Insert new message from stick drive

5) Change the message header for TTAA to “UMGC01 MWCG

6) Delete the remaining headers for parts TTBB and PPBB

7) Delete any line feeds between the parts of the message

8) Send

b. On the Metlab

1) In message composer select UM

2) Insert the message into the space provided

3) Delete headers from all parts of the message

4) Preview the message

5) Send

33. The NWS Email Data Input System (EDIS) is a procedure that allows designated meteorological data providers the capability to input weather bulletins to the National Weather Service Telecommunication Gateway (NWSTG) – also known as the Regional Telecommunication Hub (RTH), via email using the following procedures: a. Procedures for Copying Messages into Body of Email






6) Copy TEMP message and save to memory stick or floppy



12-64

b. EDIS Submission

1) The e-mail is submitted to the RTH via EDIS using a predefined e-mail address (i.e., [email protected])

2) Go to Yahoo.com

3) Click on Mail

4) Enter yahoo ID: [email protected]

5) Enter Password “metoffice”


7) The “subject line” shall contain: EDIS Message Input 8) Paste Messages from (Notepad only) in the body of email. (See Figures Below)


10) Send Message

Temp-1



Temp-2





NOTE: The iMetOS will automatically archive the NWS files (.HDR, .DAT, and .HRS) to the designated directory (c:\upperair\2008\dec). The directory Year and Month is changed automatically in iMetOS. ”DO NOT MAKE THIS DIRECTORY” The NWS files will br sent to NCDC at end of the month via FTP ONLY

38. Archiving allows the user to store ImetOS flight files in a single, compressed file. Archive the flight as follows:











12-66

















the last 2 digits of the data year (01-99) Example: mwcg1208.zip













12-68

12.4.7 Jamaica Quick Guide for Rawinsonde Flights



3. Attached (unwinder, parachute, and light if required). If regulator is not used the train cord shall be at least 25 meters.



5. Turn on the computer (upper air workstation) and sign in as the administrator “crn”.



8. Power the radiosonde with the power supply or battery (preffered) after the following steps:









12-70

















19. Wait for at least 60 data records. If the record numbers do not increase, move either the Radiosonde, or the antenna 5-10 degrees in azimuth and/or elevation. Return the Tracking Mode to Off



21. If the antenna was moved or if it was not already done, point the antenna in the general direction where the Radiosonde will go when launched. Ensure the Tracking Mode is Off

22. Set the CDU to search for frequencies between 1668 (or base) to 1690 before releasing the Radiosonde. This is because of a frqquency interference at 1694.



25. Turn on the Automatic Tracking by hitting the “4” button on the CDU or from the workstation, place the Tracking Mode to ON.

26. It is vital that the frequency and signal strength be checked prior toand immediately after the release. This should be done using the CDU at the release site.


28. Move the antenna as necessary with the CDU (or workstation computer) to reduce the tracking errors to an absolute value less than 150. Turn on Automatic Tracking by hitting the “4” button on the CDU or from the workstation (Tracking Off) Double click inside the



12-72

black area to position required. If errors do not settle to less than 20, turn off Automatic Tracking and move the antenna to the Radiosonde. Turn on Automatic Tracking. Repeat as necessary.



31. It may be necessary to correct or edit the coded messages prior to transmission

32. The NWS Email Data Input System (EDIS) is a procedure that allows designated meteorological data providers the capability to input weather bulletins to the National Weather Service Telecommunication Gateway (NWSTG) – also known as the Regional Telecommunication Hub (RTH), via email using the following procedures: a. Procedures for Copying Messages






b. EDIS Submission

1) The e-mail is submitted to the RTH via EDIS using a predefined e-mail address (i.e.,)

2) Go to cwjamaica.com

3) Webmail

4) Enter: “metservice.crn”

5) Enter Password “********”

6) Compose message




11) Send Message



Temp-1

Temp-2




36. A calculation of the Precipitable Water Content is done and the TEMP-1 and Temp-2



12-74

messages are delivered along with a plotted Tephigram chart to the Forecast Office.

37. Local Climatological forms are filled out along with relevant inventory entries

38. Archiving the flight


39. Archive the flight allows the user to store iMetOS generated files in a signle, compressed file, Archive the flight as follows:














Sending End of Month Archive Data to NCDC

1. The iMetOS v4.0.0 or later will automatically archive the NWS files to the designated directory (c:\upperair\2008\dec) unzipped. The directory Year and Month are changed automatically in iMetOS. DO NOT MAKE THIS DIRECTORY










the last 2 digits of the data year (01-99) Example: mkjp1208.zip


FTP the Data File to NCDC




4. Navigate to folder or drive with archive data (mkjp1208.zip).








12-76

12.4.8 San Andres Quick Guide for Rawinsonde Flights


2. Remove the balloon from the nozzle. Secure the balloon inside the inflation shelter by tying it to a hook.

3. Attached (unwinder and light if required). If unwinder is not used the train cord shall be at least 25 meters.



5. Turn on the computer.





b. Shake the water out of the radiosonde battery and enclose it in plastic bag.

c. Connect the B-2 battery to the voltage check (if available) until the proper 17.5 volts is reached.

d. Connect battery to the radiosonde.







13. Sonde Parameters menu appears


15. The Sonde Parameters Screen re-appears with the Sonde ID and the Calibration File Name field in with the calibration file name. “Click OK”



12-78























25. It is vital that the frequency and signal strength be checked prior to and immediately after the release. This should be done using the CDU at the rtelwase site.


27. Move the antenna as necessary to reduce the tracking errors. From the workstation (Tracking Off) “double click” inside the black area to position required. If the errors do not settle to less than 20, turn off Automatic Tracking and move antenns to the Radiosonde. Repeat as necessary.




12-80





1) TEMP message are in WordPad on iMetOS





b. EDIS Submission

1) The e-mail is submitted to the RTH via EDIS using a predefined e-mail address.

2) Compose message


4) The "subject line" shall contain: EDIS Message Input 5) Paste Messages from (Notepad only) in the body of email. (See Figures Below)

6) Send Message



Temp-1

Temp-2




35. Archive the Flight



12-82

NOTE: The iMetOS will automatically archive the NWS files (.HDR, .DAT, and .HRS) to the designated directory (c:\upperair\2008\aug). The directory Year and Month is changed automatically in iMetOS. ”DO NOT MAKE THIS DIRECTORY” The NWS files will be sent to NCDC at end of the month via FTP ONLY

36. Archive the flight by performing the following procedures:


b. Change the “To” directory to C:\IMS\iMetOS\Archives. See Figure below. o Double click on [..]: (c:\ims\imetos) o Double click on archives: (c:\ims\imetos\archive)




f. Click “Cancel”







directory (c:\upperair\2008\aug) unzipped. The directory Year and Month are changed automatically in iMetOS. DO NOT MAKE THIS DIRECTORY

2. At the end of the month open the C:\upperair\2008\aug (or current year/month) sub directive.





7. Do not right-click on the folder and “add to zip” as this will include the folder name on your PC as the path name when it extracts and your data will not be processed.

8. Make sure that the “save full path info” is not checked under the Folder Option. NOTE: If this is checked it will create a separate sub-folder and your data will not be processed.

9. The Add Menu appears with the following path (c:\upperair\2008\aug\

10. Type (xxxxmmyy) to name the zip folder according to the rules below: WHERE:

o xxxx is the 4-letter call sign for station, mm is the 2-digit data month (01-12) , yy is the last 2 digits of the data year (01-99) Example: sksp0808.zip













12-84

12.4.9 St. Maarten Quick Guide for Rawinsonde Flights









8. Power the radiosonde with the B-2 Battery after the following steps:


b. Shake the water out of the radiosonde battery and enclose in either plastic tube or bag.

c. Connect battery to the radiosonde.








14. Double click on the “…..” button and load the B2 calibration file from the B:\directory.



12-86















18. With the iMetOS, turn off “AFC” and do a “Frequency Search” for the radiosonde.


20. Take the Radiosonde to the launch area and tie it to the balloon. Allow the Radiosonde to become acclimated to the environment before releasing.


21. If the antenna was moved or if it was not already done, point the antenna in the general direction where the Radiosonde will go when launched. Ensure the Tracking Mode is Off

22. Return to the office and turn off “AFC” and do a Frequency Search” for the Radiosonde.

23. Call the Control Tower to get approval for the release.


25. Turn on Automatic Tracking by hitting the “4” button on the CDU.



28. Move the antenna as necessary with the CDU (or workstation computer) to reduce the tracking errors to an absolute value less than 150. Turn on Automatic Tracking by hitting the “4” button on the CDU or from the workstation. If the errors do not settle to less than 20, turn off Automatic Tracking and move the antenna to the Radiosonde. Turn on Automatic Tracking. Repeat as necessary.




12-88


30. Transmit an early message (UXMN) when the flight reaches around 400 hPa.


32. Messages are in WordPad on iMetOS and must be copied into Notepad before moving onto a storage media

33. Save message on a storage media (e.g. diskette, memory stick) and transmit the report through Meteorological Workstation System (METLAB) or the NWS gateway internet.

34. The NWS Emaail Data Input System (EDIS) is a procedure that allows designated meteorological data prociders the capability to input weather bulletins to the NWS Telecommunication Gateway (NWSTG) – also known as the Regional Telecommunications Hub (RTH), via email using the following procedures:

a. Procedures for copying Messages into Body of Email

1). Display the TEMP-1 message (the message is in WordPad)

2). Copy Message into Notepad

3). Leave the separator (=) signal immediately after last text for each message (TTAA, TTBB, and PPDD) without spaces (See Temp Figures below)

4). Each message must be ended with “NNNN” CAPITAL LETTERS (TTAA, TTBB, AND PPDD) on next line after the separator (-) signal (See Temp Figures below)

5). Ensure there is one line feed between eash part of Temp message )See Temp Figure Below)

6). Left-click on File>Save As and change the file name to TEMP-1 099 (ASC Number)

7). Save In (Send the file to the) 3½ disk in drive “a” or memory stick

8). Remove disk “a” drive or memory stick and place in computer with “Internet explorer”

b. EDIS Submission

1). The e-mail is submitted to the RTH via EDIS using a predefined e-mail address.

2). Go to computer with internet.

3). Go to webmail

4). Enter username: (xxxx)

5). And password: (xxxx)

6). Select Compose message

7). Message are sent to the following address: [email protected]

8). The Subject line shall contain : EDIS MESSAGE INPUT.

9). Paste Message from (Notepad Only) in the body of email (See Figures Below)

10). Ensure Temp message has been copied into body of e-mail correctly (i.e. making sure the :NNNN” are on next line after the separator (=) signal



11). Send Message

Temp-1

Temp-2



12-90


36. Use the FMC8 system to send the wind direction and speed with their corresponding heights to the Control Tower and the Flight Information Service.

37. At balloon burst (or end of flight), select “YES” to terminate the flight if screen appears.

a. Check times on TEMP-2 and print messages.

b. Send the Temp-2 report (same procedures as Temp-1).



39. Make sure the TEMP-1 and TEMP-2 along with the Standard Levels are printed

40. Calculate the ascension rate with the provided excel file (don’t save file)

41. Insert the data in the B29 form and save file.

42. Insert the data in the RTM file by using the standard levels printout and save file




1) Double click on [..]: (c:\ims\imetos)

2) Double click on archives: (c:\ims\imetos\archive)




f. Click “Cancel” after the Command Prompt window automatically closes.





46. Turn off the UPS and the power strip.



12-92











10. Type tmcm1208 (xxxxmmyy) to name the zip folder according to the rules below: WHERE:

o xxxx is the 4-letter call sign for station, mm is the 2-digit data month (01-12) , yy is the last 2 digits of the data year (01-99) Example: tmcm1208.zip





4. Navigate to folder or drive with archive data (tncm1208.zip).








12.4.10 Trinidad Quick Guide for Rawinsonde Flights






5. Turn on the computer.












12-94







12-96










18. With the iMetOS, “Turn off “AFC” and do a “Frequency Search” for the Radiosonde

19. Wait for at least 60 data records. If the record numbers do not increase, move either the Radiosonde, or the antenna 5-10 degrees in azimuth and/or elevation. Return the Tracking Mode to Off






24. Turn on Automatic Tracking by hittin the “4” button on the CDU or from the workstation, place the Tracking Mode to ON.









30. Messages are in WordPad on iMetOS and must be copied into Notepad before moving onto a storage media.

31. Copy the message to a memory stick and go to the AFTN to format the message and using the METlab computer for uplink to the ISCS







6) Copy TEMP message and save to memory stick or floppy

b. EDIS Submission

1) The e-mail is submitted to the RTH via EDIS using a predefined e-mail address (i.e.,

2) Go to Yahoo.com

3) Click on Mail

4) Enter yahoo ID:

5) Enter Password:

6) Compose message




11) Send Message



12-98

Temp-1

Temp-2






36. Archive the flight:

NOTE: The iMetOS will automatically archive the NWS files (.HDR, .DAT, and .HRS) to the designated directory (c:\upperair\2008\dec). The directory Year and Month is changed automatically in iMetOS. ”DO NOT MAKE THIS DIRECTORY” The NWS files will be sent to NCDC at the end of each month via FTP ONLY












12-100
















10. Type ttpp1208 (xxxxmmyy) to name the zip folder according to the rules below: WHERE:

o xxxx is the 4-letter call sign for station, mm is the 2-digit data month (01-12) , yy is the last 2 digits of the data year (01-99) Example: ttpp1208.zip













12-102

12.5 CHUAS IMS-1500 Quick Guide for Rawinsonde Flights (Spanish) PREPARADO POR - MARIBEL MONTERO REYES

12.5.1 República Dominicana Guía rápida para Radio sonda Vuelos 1. Infle balón 45 minutos antes de la liberación. Durante las condiciones de buen tiempo,

un rendimiento óptimo de rutina se consigue con ascensor libre que van desde 1000 a 1300 gramos. El estándar, el promedio de tasa de ascenso debería ser de 300 metros por minuto. Ajuste la libre ascensor hasta esta media se obtiene.

2. Quitar el globo de la boquilla. Asegure el balón dentro de la inflación de la vivienda mediante la vinculación a un gancho o la medición de pesos.

3. Adjunto (unwinder, paracaídas, y la luz). Si no se usa regulador del tren cable será de al menos 25 metros.


rápida liberación más lenta liberación 4. Encienda el UPS (si no lo está ya) y el poder para activar la tira de MSF.

5. Encienda el equipo (de trabajo en altitud).

6. Eliminar una radiosonda de la caja y el embalaje.

7. Abrir la lata de la Humedad y el lugar Humedad que su lugar en la radiosonda 8. Potencia la radiosonda con la fuente de alimentación o la batería (preferido), tras los

pasos siguientes: a. Preparar la batería para radiosonda exactamente 2 minutos en agua. b. Agite el agua de la batería y adjuntar radiosonda en bolsa de plástico c. Conectar el B-2 a la tensión de la batería hasta comprobar el correcto se llegue a

17.5 voltios. d. Conecte la batería a radiosonda

9. Abra el software en iMetOS modo "Vuelo Real"

10. Punto de la antena en la dirección general en que la radiosonda se baselined (AZ = 270



EL = 0) NOTA: El modo de seguimiento debe ser "OFF" Entonces la izquierda haga doble clic en el negro de la zona de azimut y / o elevación.

La antena de responder rápidamente.

11. Con el AFC Desactivado, Push "Frequency Buscar" para buscar el radiosonda.

12. Para inicializar el registro de datos de vuelo, seleccione Nuevo del menú Archivo en la barra de menú de pantalla de vuelo, de vuelo o de la pantalla la barra de herramientas. El SPS y debe ser activado para la recepción de los datos El nuevo menú.

13. Parámetros aparece Sondeo



12-104

14. Parámetros de la Sonde pantalla aparece de nuevo con la Sonde ID Pulse el "... .." y

cargar el archivo de calibración B2 de la carpeta C: \ IMS \ iMetOS \ B2 directorio. Nota: Seleccione las empresas (RSE) en caso de radiosonda es "RECON" o (CSN) si radiosonda es "NUEVO" en el menú desplegable "Tipo de archivo" y haga clic en "Abrir".

15. Parámetros de la Sonde pantalla aparece de nuevo con la Sonde ID y el Nombre del archivo de calibración completa con el nombre de archivo de calibración. "Haz clic en" Aceptar "

16. Preflight pantalla aparece con Sondeo ID insertado.



17. Introduzca el preflight los datos que figuran a continuación y haga clic en "Aceptar" a. Presión - presión de la estación se tomarán de la AP a la décima de un hectoPascal

(hPa). b. Temperatura - Registro de la temperatura de bulbo seco a la décima de un grado

Celsius. c. Humedad - El registro de la humedad a la décima de uno por ciento. d. Dirección del viento - Escriba a la décima de un grado. Para calmar los vientos, una

estimación de la dirección o el uso de 360 grados. e. La velocidad del viento - Escriba a la décima de un nudo. Para calmar los vientos,

una sola "0" se puede introducir la velocidad de viento. f. Código de nubes - Introduzca el código de cinco dígitos NhCLhCMCH. g. Tiempo (WX) Código - Introduzca el código de cuatro dígitos Wwww (dos grupos de

tiempo actual con los primeros dos dígitos utilizados para la más alta prioridad, véase el (Capítulo 11).

NOTA: No pulse el botón Guardar en la pantalla de introducción de datos Preflight hasta que la radiosonda se haya Verificado el Estado se ha completado y revisado. El Preflight de datos no se puede cambiar después de la liberación.

18. Con la iMetOS, apague "AFC" y hacer una "búsqueda de frecuencia" para la radiosonda.

19. Espere por lo menos 60 registros de datos. Si los números de registro no aumentan, o



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bien pasar la radiosonda, o la antena de 5-10 grados en azimut y / o elevación. Devuelve el modo de rastreo en Off.

20. Tome la radiosonda a la sala de la inflación y lo ate a la globo. Dejar que la radiosonda a ser aclimatadas al medio ambiente antes de la liberación. NOTA: La sonda no debe ser colocado sobre el terreno en cualquier momento. Esto puede hacer que la antena de carga que causa un cambio de frecuencia una vez que se haya puesto en libertad.

21. Si la antena se trasladó o si no se había hecho ya, Turn ON y modo de seguimiento de punto de la antena en la dirección general de la radiosonda donde irá cuando haya puesto en marcha y seguimiento Active el Mode Off.

22. Llame a la Torre de Control para obtener aprobación para la puesta en libertad si es necesario.

23. Poner en marcha el radiosonda. 24. Encienda el seguimiento automático pulsando el "4" en el CDU, o de la estación de

trabajo, coloque el modo de seguimiento a ON. 25. Es de vital importancia la frecuencia y la fuerza de la señal se comprobará antes e

inmediatamente después de la liberación. Esto debe hacerse usando la CDU en el lugar de liberación.

26. iMetOS está diseñado para reconocer los 4mb cambio en la presión que indica el inicio del vuelo.

27. Mover la antena en caso necesario, con la CDU (o equipo de trabajo) para reducir los errores de seguimiento de un valor absoluto a menos de 150. Encienda el seguimiento automático pulsando el "4" en la CDU de la estación de trabajo o "doble clic en el interior de la zona de negro a la posición requerida. Si los errores no se conforman con menos de 20, apague automático de seguimiento y mover la antena a la radiosonda. Encienda el seguimiento automático. Repita según sea necesario.

28. Asegúrese de que el IMS-1500C equipo no es un seguimiento de "los lóbulos laterales". Si se determina el seguimiento de los lóbulos laterales se está produciendo, establezca el modo de seguimiento en Manual. Gradualmente ajustar el ángulo de elevación y azimut (7 grados en cada lado), hasta un aumento significativo de la fuerza de la señal se produce. Restablecer la modalidad de rastreo automático de seguimiento.

29. Cuando el Temp-1 informe se genera y listo para la transmisión, en la verificación veces abreviado en la cabecera y datos codificados. Puede ser necesario corregir o editar el código de los mensajes antes de la transmisión.

30. Temp åre mensajes en WordPad en iMetOS, que debe ser copiado en el Bloc de notas. 31. Copiar el mensaje a un dispositivo de memoria e ir a la AFTN para formatear el mensaje

y el uso de la computadora para Metlab de enlace ascendente a la SICS. 32. Los Estados poseedores de armas nucleares del sistema de entrada de datos de correo

electrónico (SEDA) es un procedimiento que permite a los proveedores de datos meteorológicos designado la capacidad de entrada de boletines meteorológicos para el Servicio Meteorológico Nacional de Telecomunicaciones Gateway (NWSTG) - también conocido como el Centro Regional de Telecomunicaciones (CRT), a través del correo electrónico utilizando el siguientes procedimientos: a. Copia de los procedimientos de mensajes de correo electrónico en el Cuerpo.

(1) Si TEMP mensaje en WordPad en iMetOS. (2) Copia del mensaje en el Bloc de notas. (3) Dejar el separador (=) inmediatamente después de la última señal por cada

mensaje de texto (TTAA, TTBB, PPDD) sin espacios (véase Temp cifras abajo). (4) Cada mensaje debe ser terminado con "NNNN" MAYÚSCULAS (TTAA, TTBB,

PPDD) en la siguiente línea después de que el separador (=) señal. (ver cifras por debajo de Temp)



(5) Garantizar hay un avance de línea entre cada parte de los mensajes Temp. (ver cifras por debajo de Temp)

b. Presentación SEDA (1) El e-mail se presenta a la CRT a través de SEDE predefinidos utilizando un

dirección de correo electrónico (es decir, [email protected]) (2) Ir a Yahoo.com (3) Haga clic en Enviar (4) Introduzca yahoo ID: (5) Introduzca la contraseña (6) Los mensajes se envían a la siguiente dirección:

[email protected] (7) l "asunto" deberá contener: SEDA Mensaje de entrada (8) Mensajes de pasta (sólo el Bloc de notas) en el cuerpo del correo electrónico.

(Véanse los gráficos abajo) (9) Garantizar Temp mensaje ha sido copiado en el cuerpo del e-mail correctamente

(es decir, asegurarse de que la "NNNN" están en la siguiente línea después de que el separador (=) la señal).

(10) Enviar mensaje

Temp-1



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Temp-2

33. En H +45 (12:45) comprobar la THANKS (favoritos - Superior Evaluación de la Calidad de

Aire del proyecto) para "THKS". Si no está disponible por +1:00 H, reenviar mensajes. 34. En globo de ruptura (o al final del vuelo), seleccione "SI" para terminar el vuelo. 35. Enviar el informe Temp-2 utilizando mismos procedimientos que Temp-1 36. Archivo de vuelo.

NOTA: El iMetOS automáticamente el archivo NWS archivos (.HDR. DAT y. HRS) al directorio designado (c: \ upperair \ 2008 \ diciembre). El directorio de Año y Mes se cambia automáticamente en iMetOS. "NO UTILIZAR ESTE DIRECTORIO" El NWS archivos se enviarán a NCDC al final de cada mes a través de FTP SOLO.

37. Archivo permite al usuario almacenar IMetOS vuelo archivos en un único archivo comprimido. Archivo de la huida de la siguiente manera: a. IMetOS de la barra de menús, ir a Utilidades|Tienda archivos. b. Cambiar el campo "Para" al directorio C:\IMS\iMetOS\ Archivos. Véase la figura a

continuación. c. Haga doble clic en [..]: (c:\IMS\imetos) d. Haga doble clic sobre los archivos: (c:\IMS\imetos\ Archivo) e. Cambiar el "De" al directorio C:\IMS\iMetOS\Vuelos. f. Seleccione el nombre de archivo de vuelo en el "Nombre del archivo" caja

(ascensión número de vuelo). NOTA: Si hace doble clic en el número de la ascensión vuelo archivo a la "A" directorio.

g. O Haga clic en "Archivo". h. Haga clic en "Cancelar" después de la ventana Símbolo del sistema se cierra

automáticamente.



38. Ir al archivo de salida y la iMetOS 39. Apagar el ordenador. 40. Apague la tira de poder al régimen de pago único y UPS.

Fin de envío de datos al mes NCDC

1. El iMetOS v4.0.0 o posterior automáticamente el archivo de expedientes a los Estados poseedores de armas nucleares designado directorio(c:\upperair\2008\diciembre) descomprimido. El directorio de Año y Mes se cambian automáticamente en iMetOS.

NO HACER ESTE DIRECTORIO

2. A finales del mes abrir la carpeta C: \ upperair \ 2008 \ diciembre (o el año en curso / mes) sub directiva.

3. Los archivos de la carpeta debe ser mensual H, T, R o seguida de Número Ascenso (es decir, vuelo 301 sería: H301, T301 y R301)

4. Usted debe comprobar y verificar la ascensión número y la fecha. La carpeta debe contener los datos para el mes en curso solamente.

5. Ahora selecciona todos los archivos en la carpeta (Ctrl-A). 6. Haga clic derecho en archivos y seleccione la opción "añadir a Zip" o enviar a carpeta

comprimida. a. No haga clic derecho en la carpeta y "añadir a la postal", ya que incluirá el nombre

de la carpeta en su PC como el nombre de ruta cuando extractos y sus datos no serán procesadas.

b. Asegúrese de que el "guardar la ruta completa información" no está marcada la opción en virtud de la carpeta.

NOTA: Si está marcada, creará una sub-carpeta y sus datos no serán procesadas.



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7. Aparece el menú Añadir, con la siguiente ruta (c: \ upperair \ 2008 \ diciembre \ 8. Tipo mdsd1208 (xxxxmmyy) a nombre de la carpeta zip con arreglo a las normas

siguientes: DÓNDE: o xxxx es el 4-carta de llamada de la estación, mm es el 2-dígitos datos mes (01-12), es aa los 2 últimos dígitos del año de datos (01-99) ♣ Ejemplo: mdsd1208.zip

9. Cierre el programa ZIP FTP el archivo de datos a NCDC

1. Abra el Explorador de Windows usando las siguientes teclas [Tecla de Windows + E]. 2. En la barra de direcciones, escriba

ftp.ncdc.noaa.gov/pub/upload. Seleccione IR

3. De este modo, NCDC del sitio FTP en el árbol de directorios a la izquierda. 4. Navegar a la carpeta o unidad de archivo con datos (mdsd1208.zip). 5. Haga clic derecho en el archivo zip creado en el apartado anterior y seleccione la

opción "Copiar". 6. Haga clic derecho en la carpeta con el nombre: Internet Explorer -

ftp.ncdc.noaa.gov/pub/upload

7. El espacio de la derecha estará en blanco. Haga clic con el botón de que el espacio en blanco y seleccione "pegar".

8. El nombre de archivo aparecerá en el lado derecho, si tienen éxito. 9. En este momento, se ha enviado el archivo y ya está


Revision B June 2009 13-1 Precision Digital Barometer

CHAPTER 13 PRECISION DIGITAL BAROMETER

13.1 Precision Digital Barometer - General The Precision Digital Barometer, Figure 13-1, starts up automatically, and starts measuring and logging pressures, when you turn on the Power Switch. The display starts up a few seconds later. If AC power is lost, or if the charger voltage drops below 10.8VDC, the internal battery continues to operate the barometer for up to 36 hours. The display switches off when AC power is lost: you can wake up the display by pressing DISPLAY ON for a few seconds. The display switches on again once the battery is recharged (a few hours after power is restored).

Figure 13-1: Precision Digital Barometer

Power Switch. Press here to start up the PDB-1. Yellow LED indicates power is on.

Plug in PC here to input all password–protected values.

The display switches off if AC power is lost. Hold the DISPLAY ON key down for 5 seconds to switch the

Press CANCEL to return to the main display at any time, or to reject values you have entered.

Press OK to confirm values you have entered.

Press UNITS repeatedly to toggle through the display units. You can change the units of all quantities, including TR, TS.

Press DATA repeatedly to toggle through sea level; station and field pressure; sensor, station and field elevation; and pressure and density altitude.

Press INPUT to enter TR, TS, or the Pressure Reduction Ratio R. Follow the on-screen commands, and use the numeric keypad to enter values.

Use the numeric keypad to input TR, TS, and R. First press INPUT, then 1 or 2 to select the input. You need not enter the decimal point – it is already on the display.


Precision Digital Barometer June 2009 Revision B

13-2

13.2 PDB Warning Messages The Precision Digital Barometer can display a number of warning messages on the lower edge of the display. If more than two messages need to be displayed, only the code is shown. The interpretation of these codes is as follows:

Code Messages and Explanations

0. User temperature expired. You entered a value of TR, the five-minute running average temperature, more than 5 minutes ago: this value is therefore considered to be out-of-date. The altimeter setting is now calculated using a temperature-independent approximation.

1. Startup: TR, TS unfiltered. The Precision Digital Barometer powered up less than 5 minutes ago. The value of TR, the five-minute running average, may therefore be inaccurate. The altimeter setting is calculated using a temperature-independent approximation.

2. Real-time clock suspect. There may be a problem with the internal clock.

3. Not used.

4. Not used.

5. EEPROM configuration lost. There may be a problem with the EEPROM (main memory) on the main CPU board. The PDB-1 has reverted to its default configuration, which means that the Sensor Pressure is valid, but other derived values (including the Altimeter Setting) may be inaccurate.

6. 18-bit ADC suspect. The 18-bit ADC affects temperature measurements and the Precision Digital Barometer power management.

7. 12-bit ADC suspect. The 12-bit ADC affects the Precision Digital Barometer power management.

8. Real-time clock corrected. At low temperatures, the internal clock crystal runs slow. The PDB-1 monitors the temperature, and periodically corrects the clock at low temperatures. No action need be taken.

9. Not used.

10. Burst mode on. The pressure is changing rapidly, and the PDB-1 is logging this change at a 10-second rate.

11. High charger current draw. The battery charger is drawing current, indicating that the battery is running low. If AC power is lost, you should expect to see this message for some hours until the battery is completely recharged. If this message appears constantly, you probably have a bad battery.

12. Bad battery voltage. The battery voltage is running either very high (above 16 VDC) or low (below 10.7 VDC). This most likely indicates that you have a bad battery; it may indicate a bad battery charger.

13. Bad temperature reading. This indicates one of two things. First, that the PDB-1 is configured as if an external temperature sensor were present, but no such sensor is present. Second, it may indicate that the external temperature sensor is bad, or incorrectly wired.



14. Barometer not responding. The serial barometer, internal to the PDB-1 case, is not responding. The barometer may be bad, or an internal serial connection on the main CPU board may be bad.

For support, call the NWS Pressure Standards Lab, 301-713-0286.

13.3 Unpacking the Precision Digital Barometer

13.3.1 Parts List When your Precision Digital Barometer PDB-1 is delivered, check that you have received the correct parts. The following components comprise the PDB-1:

o Integrated Precision Digital Barometer assembly (Barometer Box), including keypad and display.

o 10 foot (black) communications cable with DE-9 connectors at either end for connecting the Precision Digital Barometer to a PC.

o External Air Temperature Sensor with 20-foot cable (Not needed for the Upper-air Program).

o Power cable, 6 foot.

o Pressure Hose, connector, and insect protector (Not needed for the Upper-air Program).

13.3.2 Optional External Temperature Sensor Radiation Shield (ASN G395-2) Temperature Sensor Radiation Shield (see Figure 13-2).

Figure 13-2: Optional Temperature Sensor Radiation Shield

13.4 Installing the Precision Digital Barometer

The Precision Digital Barometer PDB-1 can be permanently installed indoors or outdoors or used as a portable unit. It should be noted that even though it can be installed outdoors in extreme temperature and environmental conditions, it is still a precision instrument, and should be handled with care.



13-4

Do not drop the PDB-1, or to subject it to excessive shock or vibration. Excessive mechanical shock may cause non-repairable damage.

Do not over pressure the Precision Digital Barometer. Pressures exceeding about 1325 mbar may cause non-repairable damage.

13.4.1 Installation Installation is accomplished using the following steps:

1. Locate where the PDB-1 will reside within the Upper Air Office.

2. Optional Location: Rack mount Setup.

3. Mount external temperature sensor (Not required for Upper-air Program).

4. Pressure Connection. The PDB must measure the same (internal) environment as the Radiosonde; therefore the pressure hose to the outside is prohibited from being installed for the IMS-1500C Program).

5. Establish connections for the RS232 Serial Port, ground, and power.

13.4.2 Locating the PDB-1 In its normal configuration, the PDB-1 can be set on a table or other surface. Optional location is in a rack mount. Either location must place the PDB at the same height (+/- 1 foot) as the normal height of the Radiosonde Baselining position.

13.4.3 Setting up the Rack Mount (Option)

1. Remove the lid from the Barometer Box. The lid is removed by unclasping the front clasp. Lifting the lid and sliding the hinges apart. (See Figure 16-3).

Figure 13-313: Removing the Barometer Box Lid

(1) Slide the lid off at the hinge pin



2. Repeat the same process is reverse to connect the barometer box to the rack mount plate. (See Figure 13-4).

Figure 13-4: Mounting the Barometer Box to the Rack Mount Plate Once the rack mount plate is connected, the PDB-1 can be attached to the rack.

13.4.4 Mounting the External Temperature Sensor and Pressure Hose

NOTE: The Upper-air Program prohibits connecting the pressure connection to the outside environment). The external temperature sensor to the outside is not needed for the Upper-air Program, but can be used if desired by the local site.

1. Option. Establish a location for the external temperature sensor on the outside of the upper air office near the place where the Radiosonde will be baselined. If necessary, drill a hole through the wall for the temperature cable. Connect the external temperature sensor cable to the PDB-1. Set the external temperature sensor in a location where it will not be damaged.

13.4.5 Solar Radiation Shield Installation (Not needed for the Upper-air Program, but if installed, it can be used and does not have to be removed).

2. Attach the solar radiation shield to the tower/pole with the U-bolt supplied (see Figure 13-5).

3. Install the air temperature sensor into the radiation screen and secure with the nylon clamp provided.

4. Route the cable from the outside through the building wall to the PDB-1 inside the upper-air office securing it with cable tie wraps as you go. Do not overtighten the tie wraps as the cable could be damaged.

(2) Slide the rack mount plate on to the barometer box hinge pins with rack mount

panel tilted up

(3) When rack panel cutout is aligned with the barometer box, tilt down until seated on panel o-ring, then attach clasps to retainer plates and tighten clasp by rotating retractable clasp handles 180º. Retract until handles are out of the way. Engage and tighten the clasps



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Figure 13-5: Position of the U-bolt used to mount the Solar Radiation Shield

13.4.6 Connections Three MS style connectors are provided for connecting power, RS232 Serial Port, the external air temperature sensor (if desired by the local site), and a phone line (for the optional modem). The Pressure Connection shall not be connected to the outside environment. A grounding lug is also supplied for connecting earth ground to the PDB-1 case. See Figure 13-6 for connector layout. For connecting to a terminal or PC, a DE-9 connector is available on the front panel.

Figure 13-6: PDB-1 Connections

U-bolt

AC /DC Power

Phone Line

External Air Temperature

Earth Ground Pressure



13.5 Indicators – PDB-1 A Precision Digital Barometer PDB-1 senses and continuously indicates:

o real-time raw (sensor) barometric pressure; and

o real-time altimeter setting;

By repeatedly pressing on the unit’s front panel DATA button, you can also obtain:

o field pressure;

o station pressure;

o sea-level pressure;

o density altitude; and

o pressure altitude.

Sensor pressure is taken and displayed once every 10 seconds.

13.5.1 Operational Range The Precision Digital Barometer is environmentally sealed, and will stand up to extreme environmental conditions, including direct sunlight, salt or acid rain, and extremes of temperature. The operational temperature range is -45ºC to +50ºC (-50ºF to +130ºF), although the display will not start up at temperatures below -29ºC (-20ºF).

13.6 Precision Digital Barometer PDB-1 Specifications

13.6.1 Temperature Range Operational and storage temperature range:

o -45ºC to +50ºC (-50ºF to +130ºF) (The display does not start up at low temperatures).

13.6.2 Pressure Range

o 500 - 1100 mbar (14.75 - 32.5 inHg)

13.6.3 Pressure Measurements

o Accuracy: 0.01% of full scale

o Resolution: 0.01% of reading

o Hysteresis: 0.005% of full scale

o Long-time drift: 0.009% of full scale

o Cable of withstanding pressure up to 1.2 times full scale without damage to the PDB-1 or affecting its performance

13.6.4 Optional Temperature Sensor o Accuracy: 0.15ºC



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13.6.5 Communications o RS-232 direct serial connection or phone modem

o 9600 baud

13.6.6 Backup Battery o Good for better than 36 hours

CHUAS RAWINSONDE HANDBOOK IMS-1500C … 9-756 Rev B June 2009.pdf · sippican b2 radiosonde june...

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Transcript of CHUAS RAWINSONDE HANDBOOK IMS-1500C … 9-756 Rev B June 2009.pdf · sippican b2 radiosonde june...