MESOSCALE DISCUSSION 0300
   NWS STORM PREDICTION CENTER NORMAN OK
   1225 PM CDT SAT MAR 23 2013
   
   AREAS AFFECTED...A SMALL PART OF NRN FL
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 57...
   
   VALID 231725Z - 231800Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 57
   CONTINUES.
   
   SUMMARY...A THREAT FOR SIGNIFICANT HAIL...POTENTIALLY OF BASEBALL
   SIZE...WILL ACCOMPANY A SUPERCELL THUNDERSTORM THAT WILL TRACK
   ACROSS PARTS OF COLUMBIA...BAKER...UNION...AND
   BRADFORD...POTENTIALLY INTO CLAY...COUNTIES DURING THE NEXT HOUR.
   
   DISCUSSION...WSR-88D VOLUMETRIC SCANS SUGGEST THAT A SUPERCELL STORM
   WITH AN INCREASINGLY DISCRETE UPDRAFT IS POSING A THREAT FOR
   SIGNIFICANTLY SEVERE HAIL. WDSS-2 MESH DATA INDICATE THAT MAXIMUM
   HAIL SIZES HAVE POTENTIALLY INCREASED TO OVER 2 INCHES IN DIAMETER
   RECENTLY. WITH A CONTINUED INFLUX OF HIGH THETA-E ATOP A STABLE
   NEAR-SFC LAYER AMIDST VERY STEEP MID-LEVEL LAPSE RATES...SIGNIFICANT
   HAIL -- POTENTIALLY OF BASEBALL SIZE -- MAY ACCOMPANY THIS STORM AS
   IT TRACKS EWD/ESEWD ACROSS PARTS OF NERN FL DURING THE NEXT HOUR OR
   SO. A LOCAL SPATIAL EXTENSION OF THE WW HAS BEEN COORDINATED WITH
   THE JACKSONVILLE WEATHER FORECAST OFFICE TO ADDRESS THESE CONCERNS.
   
   ..COHEN.. 03/23/2013
   
   
   ATTN...WFO...JAX...
   
   LAT...LON   29858167 29858197 29988250 30188270 30288255 30238201
               30108166 29858167