MDL Lightning-Based MDL Lightning-Based ProductsProductsKathryn HughesKathryn HughesNOAA/NWS/OSTNOAA/NWS/OST

December 3, 2003December 3, 2003

E-mail: Kathryn.Hughes@noaa.govE-mail: Kathryn.Hughes@noaa.gov

MDL Lightning Data SourcesMDL Lightning Data Sources

Pre-1994 NLDN Pre-1994 NLDN • SUNY-AlbanySUNY-Albany• BLM – Alaska coverage BLM – Alaska coverage

NLDN archive data provided by the Global NLDN archive data provided by the Global Hydrology Resource Center / NASA 1994 Hydrology Resource Center / NASA 1994 – present– present

SFUS41 bulletins containing encrypted SFUS41 bulletins containing encrypted NLDN reports sent from NWS Gateway and NLDN reports sent from NWS Gateway and collected at NCEP supercomputers near collected at NCEP supercomputers near real-timereal-time

Meteorological Development LabMeteorological Development LabThunderstorm and Severe Thunderstorm ProductsThunderstorm and Severe Thunderstorm Products

MOS MOS • Short and extended-range forecast Short and extended-range forecast

guidance out to 192 hours in advanceguidance out to 192 hours in advance LAMP LAMP

• Very short-range forecast guidance out Very short-range forecast guidance out to 15 hours in advanceto 15 hours in advance

SCANSCAN• Nowcasting 0-3 h forecast guidanceNowcasting 0-3 h forecast guidance

Use of Lightning DataUse of Lightning Data

Define a thunderstorm eventDefine a thunderstorm event• As a As a predictandpredictand (the event we want to (the event we want to

forecast) in statistical developmentforecast) in statistical development• As a As a predictorpredictor to help forecast a to help forecast a

thunderstorm eventthunderstorm event Develop lightning climatologyDevelop lightning climatology Quality control radar reflectivity data Quality control radar reflectivity data

and severe local storm reportsand severe local storm reports Verify thunderstorm forecastsVerify thunderstorm forecasts

Creating the Gridded Lightning Datasets Creating the Gridded Lightning Datasets from Observationsfrom Observations

Strikes are summed over the appropriate time period and Strikes are summed over the appropriate time period and assigned to the center of the grid boxesassigned to the center of the grid boxes

×××××× ××

×× ××××××××

×× ××××

××××××

= thunderstorm = no thunderstorm

The MOS TechniqueThe MOS TechniqueThe EssentialsThe Essentials

A statistical techniqueA statistical technique Relates weather observations to Relates weather observations to

predictorspredictors• Numerical weather prediction (NWP) Numerical weather prediction (NWP)

modelmodel• Previous observationsPrevious observations• Geoclimatic variablesGeoclimatic variables

Multiple linear regressionMultiple linear regression Relationships forecast future weatherRelationships forecast future weather

MOSMOSCloud-to-Ground Lightning ClimatologyCloud-to-Ground Lightning Climatology

3-, 6-, 12-, and 24-3-, 6-, 12-, and 24-h Monthly h Monthly Lightning Relative Lightning Relative FrequenciesFrequencies

20-, 40-, 48-km 20-, 40-, 48-km grid resolutiongrid resolution

5-km coming soon5-km coming soon

MOS Thunderstorm Text ProductsMOS Thunderstorm Text ProductsExtended-Range GFSExtended-Range GFS

KDCA MRF MOS GUIDANCE 12/02/2003 0000 UTC KDCA MRF MOS GUIDANCE 12/02/2003 0000 UTC FHR 24| 36 48| 60 72| 84 96|108 120|132 144|156 168|180 192 FHR 24| 36 48| 60 72| 84 96|108 120|132 144|156 168|180 192 TUE 02| WED 03| THU 04| FRI 05| SAT 06| SUN 07| MON 08| TUE 09 CLIMO TUE 02| WED 03| THU 04| FRI 05| SAT 06| SUN 07| MON 08| TUE 09 CLIMO X/N 43| 26 40| 29 37| 33 39| 33 34| 25 42| 31 48| 34 47 34 50 X/N 43| 26 40| 29 37| 33 39| 33 34| 25 42| 31 48| 34 47 34 50 TMP 36| 27 35| 31 35| 35 35| 34 31| 26 37| 33 42| 36 41 TMP 36| 27 35| 31 35| 35 35| 34 31| 26 37| 33 42| 36 41 DPT 14| 11 16| 22 31| 32 31| 27 23| 18 21| 25 27| 28 29 DPT 14| 11 16| 22 31| 32 31| 27 23| 18 21| 25 27| 28 29 CLD CL| CL PC| OV OV| OV OV| OV OV| CL CL| OV CL| OV CL CLD CL| CL PC| OV OV| OV OV| OV OV| CL CL| OV CL| OV CL WND 21| 15 12| 7 8| 11 14| 17 18| 14 13| 11 10| 8 11 WND 21| 15 12| 7 8| 11 14| 17 18| 14 13| 11 10| 8 11 P12 0| 0 0| 12 49| 76 51| 58 33| 25 10| 13 13| 20 18 19 20 P12 0| 0 0| 12 49| 76 51| 58 33| 25 10| 13 13| 20 18 19 20 P24 | 1| 72| 82| 58| 27| 21| 26 29 P24 | 1| 72| 82| 58| 27| 21| 26 29 Q12 0| 0 0| 0 1| 3 2| 3 0| 0 0| 0 | Q12 0| 0 0| 0 1| 3 2| 3 0| 0 0| 0 | Q24 | 0| 2| 3| 4| 0| | Q24 | 0| 2| 3| 4| 0| | T12 1| 0 0| 0 0| 5 7| 6 3| 1 0| 0 1| 0 1 T12 1| 0 0| 0 0| 5 7| 6 3| 1 0| 0 1| 0 1 T24 | 1 | 1 | 5 | 9 | 3 | 0 | 1 T24 | 1 | 1 | 5 | 9 | 3 | 0 | 1 PZP 4| 6 15| 29 34| 39 18| 14 15| 12 11| 19 11| 16 2 PZP 4| 6 15| 29 34| 39 18| 14 15| 12 11| 19 11| 16 2 PSN 82| 94 70| 60 27| 5 3| 27 49| 62 34| 34 37| 17 0 PSN 82| 94 70| 60 27| 5 3| 27 49| 62 34| 34 37| 17 0 PRS 15| 0 15| 11 21| 7 13| 12 4| 3 1| 1 0| 4 2 PRS 15| 0 15| 11 21| 7 13| 12 4| 3 1| 1 0| 4 2 TYP S| S S| Z Z| Z R| RS S| S S| S S| R RTYP S| S S| Z Z| Z R| RS S| S S| S S| R R

MOS Thunderstorm Text ProductsMOS Thunderstorm Text Products Short-Range ProductsShort-Range Products

GFS and Eta-based messagesGFS and Eta-based messages

KDCA AVN MOS GUIDANCE 7/08/2003 0000 UTC DT /JULY 8 /JULY 9 /JULY 10 / HR 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 18 00 X/N 95 76 90 72 86 TMP 77 75 78 87 92 92 87 82 79 77 79 85 87 86 81 77 75 73 75 83 80 DPT 72 71 72 74 74 74 74 75 75 73 74 73 73 73 72 72 71 70 70 72 73 CLD BK SC BK BK BK SC BK BK BK BK OV OV OV OV OV OV OV OV OV OV OV WDR 25 25 25 27 25 23 24 25 27 28 26 25 25 26 27 28 34 36 01 17 19 WSP 07 05 06 08 09 10 10 08 07 05 04 05 07 07 07 05 05 04 04 06 09 P06 1 4 10 8 12 22 49 35 17 15 37 P12 13 12 54 42 44 Q06 0 0 0 0 0 0 3 1 0 0 2 Q12 0 0 3 1 2 T06 3/ 0 9/ 0 48/26 32/11 13/ 1 12/ 1 35/26 26/ 8 7/ 0 34/23 T12 11/ 0 56/26 34/ 1 55/26 25/ 0 CIG 7 7 7 7 7 7 7 7 7 7 6 6 6 5 6 6 6 5 4 5 5 VIS 7 7 7 7 7 7 7 7 7 7 6 6 6 6 6 6 6 6 5 6 5 OBV N N N N N N N N N N HZ HZ HZ N HZ HZ BR BR BR HZ BR

MOS Thunderstorm Graphical ProductsMOS Thunderstorm Graphical Products24-h forecast ending 1200 UTC 4 Dec 200324-h forecast ending 1200 UTC 4 Dec 2003

Web-based Web-based graphicsgraphics

40-km GRIB files 40-km GRIB files availableavailable

6-, 12-, 24-h 6-, 12-, 24-h forecast periodsforecast periods

Operational from Operational from Eta and GFS Eta and GFS model outputmodel output

Lightning observations are used to create Lightning observations are used to create conditional severe weather predictandsconditional severe weather predictands

Given the occurrence of lightning, this is the probability of a severe Given the occurrence of lightning, this is the probability of a severe thunderstorm event (wind, hail, tornado)thunderstorm event (wind, hail, tornado)

Forecast VerificationForecast VerificationEta-based 3-h MOS forecasts on 20-km gridEta-based 3-h MOS forecasts on 20-km grid

26 Aug 2002 21-24h26 Aug 2002 21-24h

LAMPLAMPLocalized Aviation MOS ProgramLocalized Aviation MOS Program

A very short-range forecast programA very short-range forecast program

NLDN data defines a LAMP thunderstormNLDN data defines a LAMP thunderstorm• 1 or more strikes in the appropriate grid box, during a 1- 1 or more strikes in the appropriate grid box, during a 1-

or 2-hr time period, out to 15 hours in advance.or 2-hr time period, out to 15 hours in advance. Cloud-to-ground lightning strikes may be used as Cloud-to-ground lightning strikes may be used as

potential predictors by the linear regression potential predictors by the linear regression programprogram

Monthly relative frequencies will be used as Monthly relative frequencies will be used as potential predictorspotential predictors

Lightning strike reports are used to quality control Lightning strike reports are used to quality control radar reflectivity dataradar reflectivity data

Warm Season Relative Frequency (%) of Lightning eventsWarm Season Relative Frequency (%) of Lightning events

24 15-min time periods : 10-km grid resolution

SCAN SCAN System for Convection Analysis and NowcastingSystem for Convection Analysis and Nowcasting

Operational 0-3 hour convective Operational 0-3 hour convective Weather ForecastsWeather Forecasts

Hourly output for the conterminous Hourly output for the conterminous United StatesUnited States

Probability of 2 or more lightning Probability of 2 or more lightning strikes within a 40-km square regionstrikes within a 40-km square region

NLDN lightning strike observations NLDN lightning strike observations are used as predictorsare used as predictors

Probability of 2 or more CG lightning strikes during a 0-3 h Probability of 2 or more CG lightning strikes during a 0-3 h forecast period 2100-0000 UTC 2-3 May 1997forecast period 2100-0000 UTC 2-3 May 1997

Future WorkFuture Work

Alaska MOS thunderstorm guidanceAlaska MOS thunderstorm guidance

Support for the National Digital Forecast Support for the National Digital Forecast Database (NDFD) at 5-km resolutionDatabase (NDFD) at 5-km resolution

Investigate oceanic data for future guidance Investigate oceanic data for future guidance in Hawaii and the Caribbeanin Hawaii and the Caribbean

Investigate use of a total lightning Investigate use of a total lightning observation, in addition to the ground-based observation, in addition to the ground-based cloud-to-ground lightning observationcloud-to-ground lightning observation

http://www.nws.noaa.gov/mdl/synop