MESOSCALE DISCUSSION 1084 NWS STORM PREDICTION CENTER NORMAN OK 1245 PM CDT WED JUN 06 2012 AREAS AFFECTED...NRN FL...FAR SRN GA...FAR SERN AL CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY VALID 061745Z - 062015Z PROBABILITY OF WATCH ISSUANCE...20 PERCENT SUMMARY...ISOLATED INSTANCES OF MARGINALLY SVR WIND GUSTS MAY OCCUR IN ASSOCIATION WITH SCATTERED THUNDERSTORMS THIS AFTERNOON. CONVECTION WILL BE RATHER DISORGANIZED...AND THE ISSUANCE OF A WW IS UNLIKELY. DISCUSSION...LATEST SFC MESOANALYSIS INDICATES A FRONT EXTENDING E-W ACROSS SRN GA/AL/MS...WITH A WEAK MESOLOW OVER S-CNTRL AL. SOUTH OF THE FRONT...AREAS OF STRONG INSOLATION CONTINUE AMIDST A MOIST AIR MASS FEATURING PW VALUES OF 1.6-1.8 INCHES PER GPS DATA AND SFC DEWPOINTS IN THE UPPER 60S TO THE LOWER 70S. AS LOW-LEVEL LAPSE RATES STEEPEN IN THIS AREA...MLCAPE VALUES WILL INCREASE TO 1500-2500 J/KG /PER MODIFIED 12Z TALLAHASSEE RAOB/. AS SUCH...CONVECTION WILL INCREASE IN COVERAGE AND INTENSITY THROUGH THE AFTERNOON OWING TO THE INCREASING INSTABILITY AND ASCENT INVOF /1/ THE FRONTS AND MESOLOW.../2/ A DEVELOPING SEA BREEZE BOUNDARY...AND /3/ OUTFLOW BOUNDARIES ACROSS NRN FL ASSOCIATED WITH ONGOING CONVECTION. CONVECTION WILL MAINLY BE DISORGANIZED WITH WEAK DEEP SHEAR IN PLACE -- I.E. 0-6-KM BULK SHEAR MAGNITUDE OF 20 KT PER TALLAHASSEE VWP DATA -- SUPPORTING A PULSE TO OCCASIONALLY MULTICELLULAR CONVECTIVE MODE. ISOLATED INSTANCES OF MARGINALLY SVR WIND GUSTS CANNOT BE RULED OUT WITH THE STRONGEST STORMS...AS DCAPE VALUES INCREASE /MAINLY OVER WRN AREAS/ WHILE A POCKET OF MID-LEVEL DRY AIR CROSSES THE AREA WITHIN THE BASE OF AN ERN CONUS TROUGH. HOWEVER...WEAK DEEP SHEAR...WEAK DEEP FORCING FOR ASCENT...AND LIMITED MID-LEVEL LAPSE RATES SHOULD MITIGATE THE SVR THREAT. ..COHEN/WEISS.. 06/06/2012 ATTN...WFO...CHS...TBW...JAX...TAE...MOB...
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