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Date: 16 Oct 08Chair: Mr. Jeffrey AtorExec Secretary: Lt Col Chaz Harris, USAF

•Telecon # 888-680-9581, pass code 535430#• Web Meeting:  https://connect.dco.dod.mil/mc16oct

Working Group

for

Meteorological Codes

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Welcome

• Administrative remarks

– Meeting is being recorded

– Rest rooms: keys are on counter at front door; men left, ladies past elev. then right

– Emergency evacuation – see map

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Facility Diagram

• Ele

va

tors

•MEN

•WOMEN

•Toilet•Kit

•Copier

•Fax

•DFC • US

AF

•FC

•Meeting• room

Meet in small park behind McDonalds

KEYS

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Agenda

• Introductions, attendance, Draft ROA

• Review Open Action Items from ROA: BUFR, GRIB, Product Catalog & FMH3

• WMO Codes Meeting Briefing (then break?)

• Review Three Proposed FMH-1 Changes: LWE, Ice Accretion and Admin

• Discussion of SKC vs CLR (USAF)

• Review Action Items and Conclude Meeting

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• Introductions around room and on telephone

Introductions and Attendance

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• Approval of draft Record of Actions from Feb 08 sent via email

Approve Draft ROA

7Previous Open Action Items

• 4 from 2006; 2 from 2007; 1 in 2008 - new

• AI 06-3.2 National BUFR Migration Plan– Confirmed OPR: Mr Branski, NWS CIO– Should be done in the next year (OFCM task)– Recommend: WG request white paper by 1 Jan

• AI 06-1.1 Sample BUFR & CREX Data– OPR: NWS, Mr Walt Smith– Some data provided; any more needed?– Recommend close

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Previous Open Action Items - 2006

• AI 06-3.4 – Communication Nulls– OPR: NWS, Mr Walt Smith– WMO does not require nulls; who does?– Is this really a MC area of concern?– Recommend?

• AI 06-3.5 – Product Catalog– OPR: NWS, Mr Walt Smith– Stems from WMO Volume C; drives metadata– Recommend?

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Previous Open Action Items - 2007

• AI 07-2.1 – GRIB1 Migration Status– OPR: NWS, Mr Walt Smith– Both a user (input) and producer (output) issue– NCEP std is G2 but some products (eg avn) are

still G1; ICAO/FAA to GRIB2 by 2014; AF G1 input not needed, output still G1 but will change by ?; Navy to change to G2 by ?

– Recommend WG continue to monitor

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Previous Open Action Items – 2007 cont.

• AI 07-2.2 – FMH3 Changes– OPR: OFCM, LtCol Harris– OFCM reviewed changes but needs clarity– NWS, Mr Marsh has a “Big Idea”

– Recommend: ??

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Previous Open Action Items – 2008

• AI 08-1.1 – WIST Outreach– OPR: OFCM, LtCol Harris– Discussed with WIST OFCM rep and made an

offer to assist with their data std; no request …yet

– Recommend: Close

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WMO Codes Brief

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Break?

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• Snow and Drizzle and Liquid Water Equivalent (LWE) Rates

• OPR: FAA, Mr Albersheim, Mr Rovito• FAA requests pre-approved by WG/MC • Changes will not be made official until the

FAA has completed all preliminary work (e.g. safety risk analysis) and sends a formal request to OFCM asking for the change to FMH-1.

Proposed Changes – FMH-1 LWE

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• 8.4 Present Weather Observing Standards; 8.4.1 Qualifiers; a. Intensity/Proximity.; (1)Intensity of Precipitation (b) Intensity of Snow and Drizzle

Change: Intensity of Snow or Drizzle Based on Visibility Intensity Criteria

Light Visibility > 1/2 mile.

Moderate Visibility > 1/4 mile but <= 1/2 mile.

Heavy Visibility <= 1/4 mile

To: The intensity of snow shall be based on the reported liquid water equivalent (LWE) rate if available in accordance with Table 8-4.1 when occurring alone.

 Intensity of Snow Based on LWE Rate Intensity Criteria

Light LWE rate < 1.0 mm/h

Moderate LWE rate >= 1.0 mm/h but < 2.5 mm/h

Heavy LWE rate >= 2.5 mm/h

Proposed Changes – FMH-1 LWE cont

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To (continued) :

The intensity of drizzle shall be based on the reported liquid water equivalent (LWE) rate if available in accordance with Table 8-4.2 when occurring alone.

 Intensity of Drizzle Based on LWE Rate Intensity Criteria

Light LWE rate < 0.254 mm/h

Moderate LWE rate >= 0.254 mm/h but < 0.508 mm/h

Heavy LWE rate >= 0.508 mm/h

• Issue: Units???• Keep current visibility table if no LWE available

• Comments in section 8.4??

Proposed Changes – FMH-1 LWE cont

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Change #2: 2.5.2 Aviation Selected Special Weather Report (SPECI); a. Criteria for SPECI

 CHANGE

  (6) PRECIPITATION.

(a) hail begins or ends.

(b) freezing precipitation begins, ends, or changes intensity.

(c) ice pellets begin, end, or change intensity.

 

TO

  (6) PRECIPITATION.

(a) hail begins or ends.

(b) freezing precipitation begins, ends, or changes intensity.

(c) ice pellets begin, end, or change intensity.

(d) snow begins, ends or changes intensity.

Proposed Changes – FMH-1 LWE cont

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Change #3:

• Include the LWE rate in the remarks section of the METAR and SPECI

• Include a flag indicating if the precipitation intensity is based on visibility or LWE rate in the METAR and SPECI

• FMH Location?• Propose to ICAO as the standard?

• Plan: FAA to finalize wording of change, OFCM will perform official coordination again pre-approval

Proposed Changes – FMH-1 LWE cont

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• OPR: FAA, Mr Albersheim (?)• Change: Ch. 12, Para 12.7.2 (Additive data) add new

paragraph k using FAA field manual language 7900.5b- 1-, 3- and 6-Hourly Ice Accretion Amount, I1nnn, I3nnn, I6nnn

- At automated stations with a freezing rain sensor, this remark is included in METAR/SPECI reports for the ice accretion amount that has occurred in hundredths of an inch during the last 1-hour (I1nnn), 3-hour (I3nnn), and 6-hour (I6nnn) period. No manual backup is required.

- Plan: FAA to finalize wording of change, OFCM will perform official coordination

Proposed Changes - Ice accretion

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Proposed FMH-1 Change - Administrative• Introduced last MC meeting, Feb 08

• Change in Ch. 2, Para 2.5.2a8e: “The lowest standard instrument approach procedure minimum as published in the National Ocean Service (NOS) U.S. Terminal Procedures. If none published, use 200 feet.”

• To: “The lowest standard instrument approach procedure minimum as published in the FAA National Aeronautical Charting Office (NACO) U.S. Terminal Procedures. If none published, use 200 feet.”

• Update acronym list: Remove the “NOS” and add “NACO”

• Discussion? Concur?

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Proposed FMH-1 Changes Aproach

• Timing & grouping (LWE, Ice accretion, admin)

•OPRs work with OFCM to draft change

•Staff change to WG/AOS• Higher if bigger issue (e.g. LWE go to ICMSSR)

• Out from OFCM to agencies for staffing, comment resolution, etc

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USAF

• SKC versus CLR discussion

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Open Discussion & Wrap Up

• Alibis? New items?

•Review of new action items

•Conclude