MESOSCALE DISCUSSION 0265
   NWS STORM PREDICTION CENTER NORMAN OK
   0739 PM CDT WED MAR 23 2011
   
   AREAS AFFECTED...MIDDLE AND ERN TN/WRN NC/SWRN VA/FAR NRN AL AND FAR
   NRN GA
   
   CONCERNING...TORNADO WATCH 56...58...
   
   VALID 240039Z - 240145Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 56...58...CONTINUES.
   
   ...WW 58 AND SRN EXTENT OF WW 56...
   --- THREAT FOR TORNADOES CONTINUES ACROSS PARTS OF MIDDLE INTO ERN
   TN...WITH THIS THREAT ADVANCING INTO NRN AL SUCH THAT AN AREAL
   EXTENSION OF WW 58 HAS OCCURRED PER RECENT SPC-WFO COORDINATION. ---
   
   REGIONAL RADAR IMAGERY SHOWED A BROKEN LINE OF STORMS EXTENDING FROM
   SWRN VA THROUGH NERN TO SRN MIDDLE TN NEAR THE AL BORDER.  ALTHOUGH
   THE AIR MASS ALONG AND E TO S OF THIS LINE OF STORMS REMAINS ONLY
   MARGINALLY UNSTABLE...STRONG FORCING FOR ASCENT WITHIN EXIT REGION
   OF 100 KT WLY MIDLEVEL JET OVER TN COMBINED WITH 50-65 KT EFFECTIVE
   BULK SHEAR CONTINUES TO SUPPORT STORM ORGANIZATION.  IN ADDITION...
   LOW LEVEL SHEAR /300-500 M2/S2 OF EFFECTIVE SRH/ EXTENDING FROM NRN
   AL TO ERN TN TO WRN NC SUPPORTS THE CONTINUED THREAT FOR TORNADOES
   YET THIS EVENING.
   
   ...NRN EXTENT OF WW 56...
   WEAKER INSTABILITY WITH NWD EXTENT ACROSS WW 56...LIKELY DUE TO
   EARLIER CONVECTION MOVING THROUGH THIS REGION AND NOW LOCATED E OF
   WW 56...SUGGESTS THE OVERALL SEVERE WEATHER THREAT SHOULD CONTINUE
   TO WANE.  THE EXCEPTION MAY BE WITH ACTIVITY CURRENTLY LOCATED OVER
   FAR SWRN VA IN SCOTT COUNTY...WITH THESE PARTICULAR STORMS AFFECTING
   THE BORDER REGION OF SWRN VA/NERN TN/NWRN NC.
   
   ..PETERS.. 03/24/2011
   
   
   ATTN...WFO...AKQ...LWX...RAH...RNK...RLX...GSP...MRX...JKL...
   FFC...OHX...BMX...HUN...MEG...
   
   LAT...LON   35158834 35388716 35948675 36308606 36668387 36728303
               37028209 37318138 37508049 38108001 38227968 37687831
               36407896 35998084 35188246 34978321 34538518 34418671
               34368801 35158834