MESOSCALE DISCUSSION 0452
   NWS STORM PREDICTION CENTER NORMAN OK
   0939 AM CDT SAT APR 16 2011
   
   AREAS AFFECTED...PORTIONS ERN GA...CENTRAL/ERN CAROLINAS...SERN AND
   EXTREME S-CENTRAL VA.
   
   CONCERNING...TORNADO WATCH 149...
   
   VALID 161439Z - 161645Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 149 CONTINUES.
   
   WW MAY BE CLEARED BEHIND SFC COLD FRONT DELINEATED BELOW.  SVR
   POTENTIAL FCST TO INCREASE THROUGH REMAINDER MORNING OVER ERN
   PORTIONS WW...AS WELL AS EWD ACROSS COASTAL PLAIN AND NEWD ALONG
   PIEDMONT INTO PORTIONS VA.  ADDITIONAL WW ISSUANCE IS BEING
   CONSIDERED FOR THOSE AREAS AS SHEAR AND INSTABILITY EACH STRENGTHEN
   THROUGH MIDDAY.
   
   14Z SFC MESOANALYSIS SHOWS COLD FRONT FROM CENTRAL WV SWD ACROSS
   EXTREME WRN VA ...NWRN SC...NEAR GMU...DBN...SWWD ACROSS APALACHEE
   BAY.  COLD FRONT WILL ACT AS WRN BOUND FOR ORGANIZED SVR POTENTIAL
   AS IT MOVES EWD ACROSS WW AND SURROUNDING AREAS.  DIFFUSE WARM FRONT
   -- WHICH ALSO ACTS AS DIFFERENTIAL HEATING ZONE ALONG SRN EDGE OF
   DENSE/MULTILEVEL CLOUD COVER -- WAS ANALYZED INVOF SC/NC
   BORDER...AND WILL LIFT NWD ACROSS NC AND PERHAPS PORTIONS SRN VA
   THROUGH MID-DAY.  WARM SECTOR WILL REMAIN CHARACTERIZED BY SFC DEW
   POINTS RANGING FROM UPPER 60S F SERN GA TO COASTAL SC...INCREASING
   TO UPPER 50S AND LOW 60S OVER NRN NC AND VA AS WARM FRONT PASSES AND
   MORE SUSTAINED BREAKS APPEAR IN CLOUD COVER.  THIS ALSO WILL FOSTER
   STRONGER SFC DIABATIC HEATING IN WARM-SECTOR AIR MASS THAT ALREADY
   APPEARS MINIMALLY CAPPED...BASED ON MODIFIED RAOBS AND RUC
   SOUNDINGS.  MLCAPE SHOULD RISE TO RANGE FROM AROUND 500 J/KG OVER
   SERN VA/NERN NC...TO NEAR 1500 J/KG OVER CHS-SAV CORRIDOR.  AS THIS
   OCCURS...RESULTING IN DEEPENING BUOYANT PROFILE THROUGH
   TROPOSPHERE...DEEP-LAYER SHEAR WILL INCREASE  WITH APCH OF MID-UPPER
   TROUGH NOW OVER TN VALLEY REGION.  BOTH PROCESSES SHOULD BOOST
   EFFECTIVE SHEAR TO 55-70 KT RANGE OVER MUCH OF NC/SRN VA AND 45-60
   KT ACROSS SC.  SRH AND LOW-LEVEL VORTICITY WILL REMAIN MAXIMIZED
   NEAR WARM FRONT...ALTHOUGH HODOGRAPHS WILL REMAIN SUFFICIENTLY LARGE
   TO SUPPORT SUPERCELL/TORNADO POTENTIAL TO ITS S AS WELL.
   
   ..EDWARDS.. 04/16/2011
   
   
   ATTN...WFO...AKQ...MHX...RAH...ILM...RNK...CHS...CAE...GSP...
   JAX...FFC...
   
   LAT...LON   31938316 32888238 34678182 35598138 36777892 37507737
               37557636 36957599 35047730 33767795 33877803 33877857
               33287918 33107916 32598002 31728119 31938316