MESOSCALE DISCUSSION 1431
NWS STORM PREDICTION CENTER NORMAN OK
0218 PM CDT FRI JUL 23 2010
AREAS AFFECTED...AL/FL PANHANDLE COAST...EXTREME SRN/SERN AL AND
SWRN GA
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY VALID 231918Z - 232015Z
A THREAT FOR ISOLATED DAMAGING WIND GUSTS WILL EXIST ACROSS THE
REGION. A WW IS NOT CURRENTLY ANTICIPATED.
VERY STRONG BOUNDARY LAYER HEATING HAS RESULTED IN SFC TEMPERATURES
WARMING INTO THE UPPER 90S. VISIBLE SATELLITE IMAGERY AND SFC OBS
REVEAL A CONFLUENCE ZONE EXTENDING FROM NEAR 15 SW PNS TO 10 ESE DHN
TO 20 SSE CSG...WITH ISOLATED THUNDERSTORMS FORMING ALONG THIS LINE.
ENHANCED DEEP-LAYER ELY FLOW ALONG THE NRN PERIPHERY OF A CLOSED
MID-LEVEL CIRCULATION PROGRESSING WWD ACROSS THE GULF WILL EXIST
ACROSS THE FL PANHANDLE...YIELDING EFFECTIVE BULK SHEAR VALUES
AROUND 30 KTS. 18Z TLH SOUNDING INDICATES STEEPENING LOW-LEVEL LAPSE
RATES IN RESPONSE TO BOUNDARY LAYER HEATING...AND GIVEN SFC T-TD
SPREADS OF 20-30 DEG F ACROSS THE REGION...THE POTENTIAL FOR
DAMAGING WIND GUSTS WILL EXIST WITH THE STRONGER THUNDERSTORMS.
HIGH RESOLUTION SHORT-TERM MODEL SOLUTIONS REMAIN INCONSISTENT WITH
THE EVOLUTION OF CONVECTION ACROSS THE AREA LATER THIS AFTERNOON AND
EVENING...BUT THERE IS SOME SIGNAL INDICATING THAT THUNDERSTORMS MAY
ATTEMPT TO ORGANIZE INTO A BROKEN LINE ACROSS THE ERN FL PANHANDLE
INTO SRN AL LATER THIS AFTERNOON. GIVEN ANOMALOUSLY STRONG
DEEP-LAYER SHEAR ALREADY IN PLACE...THIS SCENARIO IS NOT OUT OF THE
QUESTION...AND IF THIS WERE TO MATERIALIZE...A MORE WIDESPREAD
THREAT FOR DAMAGING WINDS MAY EXIST LATER THIS EVENING.
HOWEVER...WITH THE EXPECTED ISOLATED NATURE OF THUNDERSTORMS OVER
THE NEXT FEW HRS...A WW IS NOT CURRENTLY ANTICIPATED.
..ROGERS.. 07/23/2010
