MESOSCALE DISCUSSION 0735
   NWS STORM PREDICTION CENTER NORMAN OK
   0157 PM CDT WED MAY 06 2009
   
   AREAS AFFECTED...CNTRL AND ERN AL THROUGH NRN AND CNTRL GA
   
   CONCERNING...TORNADO WATCH 254...
   
   VALID 061857Z - 062030Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 254 CONTINUES.
   
   THE THREAT FOR ISOLATED DAMAGING WIND AND ISOLATED TORNADOES WILL
   PERSIST NEXT FEW HOURS...MAINLY FROM S CNTRL AL THROUGH CNTRL AND
   NERN GA.
   
   SQUALL LINE EXTENDS FROM NW GA NEAR ATLANTA SWWD THROUGH S CNTRL AL.
   NRN PORTION OF LINE IS MOVING EAST AT AROUND 25 KT WHILE SRN PORTION
   HAS SLOWED ITS SWD PROGRESS AND IS ORIENTED MORE PARALLEL TO THE
   DEEP LAYER FLOW. PRE-CONVECTIVE WARM SECTOR IS MARGINALLY TO
   MODERATELY UNSTABLE WITH 800-1200 J/KG MLCAPE AND 6.5-7 C/KM MID
   LEVEL LAPSE RATES. TENDENCY HAS BEEN FOR BOUNDARY LAYER FLOW TO VEER
   AHEAD OF THE LINE...AND THIS HAS RESULTED IN A DECREASE IN STORM
   RELATIVE INFLOW AND 0-1 KM HELICITY. AS A RESULT...STORMS ON NRN END
   OF LINE HAVE UNDERGONE A TEMPORARY WEAKENING. POTENTIAL EXISTS FOR
   STORMS TO RE-INTENSIFY AS THEY DEVELOP EWD THROUGH THE DESTABILIZING
   WARM SECTOR. THE VEERED BOUNDARY LAYER FLOW COULD BE PARTLY THE
   RESULT OF LEAD IMPULSE LIFTING NE THROUGH ERN TN VALLEY REGION. AN
   UPSTREAM SHORTWAVE TROUGH IS MOVING EWD THROUGH THE LOWER MS VALLEY.
   IT REMAINS UNCERTAIN HOW THE LOW LEVEL WINDS WILL RESPOND TO THIS
   FEATURE. HOWEVER...AT LEAST A MODEST INCREASE IN 0-2 KM SHEAR COULD
   STILL OCCUR THIS AFTERNOON WHICH WILL MAINTAIN A THREAT FOR ISOLATED
   TORNADOES...ESPECIALLY GIVEN RECENT TENDENCY FOR STORMS TO BECOME
   MORE DISCRETE.
   
   ..DIAL.. 05/06/2009
   
   
   ATTN...WFO...CAE...GSP...FFC...BMX...
   
   LAT...LON   34458251 33898235 32088453 32088589 32618523 33448447
               34278381 34458251