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Science and Technology Seminar

Developing Gridded Forecast Guidance

For Warm Season Lightning Over Florida Using

The Perfect Prognosis Method and Mesoscale Model Output

Phillip Shafer

and

Henry Fuelberg

Department of Meteorology

Florida State University

Phillip Shafer and Henry Fuelberg will describe the development of a high-resolution, gridded forecast guidance product for warm season cloud-to-ground (CG) lightning in Florida. Four warm seasons of analysis data from the 20-km Rapid Update Cycle (RUC) and lightning data from the National Lightning Detection Network are used to examine relationships between observed atmospheric parameters and the spatial and temporal patterns of CG lightning over Florida. The most important RUC-derived parameters are then used in a perfect prognosis (PP) technique to develop equations producing 3-hourly spatial probability forecasts for one or more CG flashes, as well as the probability of exceeding various flash count percentile thresholds. They will also evaluate the lightning forecast scheme when applied to output from three mesoscale models during an independent test period (the 2006 warm season). The evaluation is performed using output from NCEP’s 13-km RUC, the NCEP 12-km NAM-WRF, and local runs of WRF for a domain over South Florida that were initialized with NCEP 1/12th degree sea-surface temperature (SST) data and local data from WRF-LAPS.

Wednesday, April 04, 2007

2:00 3:00 P.M. ET

SSMC #2, Room 2358

Probability of one or more flashes based on RUC analyses and lightning

strike verification for 4-5 June 2004 between 1800-2059 UTC.

(Contact: Bob Glahn at (301) 713-1768)