MESOSCALE DISCUSSION 0469
   NWS STORM PREDICTION CENTER NORMAN OK
   0322 PM CDT MON APR 13 2009
   
   AREAS AFFECTED...SERN GA...SRN SC...NRN FL AND FL PANHANDLE
   
   CONCERNING...TORNADO WATCH 149...
   
   VALID 132022Z - 132145Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 149 CONTINUES.
   
   THE TORNADO AND WIND DAMAGE THREAT SHOULD CONTINUE ACROSS TORNADO
   WATCHES 149 AND 150. THE MCS ASSOCIATED WITH THE SEVERE THREAT
   SHOULD MAINTAIN INTENSITY EWD INTO THE NRN FL PENINSULA BY EARLY
   THIS EVENING. TORNADO WATCH 149 WILL BE LOCALLY EXTENDED BY THE
   TALLAHASSEE WEATHER FORECAST OFFICE. HOWEVER...A NEW TORNADO WATCH
   WILL LIKELY BE NECESSARY TO REPLACE THE CURRENT WATCHES BY 23Z.
   
   ACCORDING TO RUC ANALYSIS...INSTABILITY HAS INCREASED JUST AHEAD OF
   THE LARGE MCS WITH MLCAPE VALUES NOW ABOVE 1000 J/KG ACROSS THE NRN
   FL PANHANDLE AND ACROSS MOST OF NRN FL. THE INSTABILITY ALONG WITH
   LARGE-SCALE ASCENT ASSOCIATED WITH A SHORTWAVE TROUGH EVIDENT ON
   WATER VAPOR IMAGERY AND LIFT WITH A 40 TO 50 KT LOW-LEVEL JET SHOULD
   SUSTAIN THE MCS ESEWD INTO NRN FL LATE THIS AFTERNOON INTO EARLY
   THIS EVENING. THE TALLAHASSEE WSR-88D VWPS APPEARS TO BE SAMPLING
   THE LOW-LEVEL JET WELL SHOWING ABOUT 25 KT OF 0-1 KM SHEAR AND 0-3
   KM SRH VALUES OF 350 TO 400 M2/S2. THIS ALONG WITH STRONG VERTICAL
   SHEAR SHOULD BE FAVORABLE FOR TORNADOES WITH SUPERCELLS AND BOWING
   LINE-SEGMENTS FOR THE REMAINDER OF THE AFTERNOON INTO EARLY THIS
   EVENING. WIND DAMAGE WILL BE LIKELY WITH THE MORE INTENSE BOWING
   LINE SEGMENTS ALONG THE AXIS OF THE LOW-LEVEL JET. AN ISOLATED WIND
   DAMAGE THREAT MAY ALSO DEVELOP SEWD ACROSS NRN FL WHERE ABUNDANT
   MOISTURE IS PRESENT AND LOW-LEVEL LAPSE RATES ARE STEEPER THAN AREAS
   TO THE NORTH.
   
   ..BROYLES.. 04/13/2009
   
   
   ATTN...WFO...CHS...JAX...FFC...TAE...MOB...
   
   LAT...LON   29938091 29918127 29658120 29628153 29888162 29738207
               29828217 29938249 29668267 29608298 29348313 29218351
               29728401 29528446 29278502 29398551 29668578 29868604
               30098641 30978637 31028617 31168609 31228572 31308558
               31308511 31498506 31518485 31628485 31638456 31938459
               31868319 32258272 32308238 32148172 32188112 31878058
               31268094 30688112 29938091