MESOSCALE DISCUSSION 0497
   NWS STORM PREDICTION CENTER NORMAN OK
   0651 PM CDT WED APR 20 2011
   
   AREAS AFFECTED...NRN MS INTO NRN AL
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 202351Z - 210115Z
   
   A NEW WW COULD BE REQUIRED OVER MUCH OF NRN MS INTO CNTRL/NRN AL FOR
   HAIL...BUT ALSO FOR A POTENTIAL WIND THREAT DEVELOPING.
   
   LATEST RADAR SHOWS STORMS JUST CROSSING THE MS RIVER CONGEALING INTO
   A LINEAR STRUCTURE...WHILE A GENERAL INCREASE IN ISOLATED STORMS
   CONTAINING HAIL WAS ALSO OCCURRING TO THE E.  AT LEAST ISOLATED HAIL
   IS EXPECTED TO AFFECT PORTIONS OF NRN AL AS THE ACTIVITY MOVES
   SLOWLY EWD OUT OF MS. HOWEVER...THERE IS CONCERN A WIND THREAT MAY
   BE DEVELOPING OUT OF THE ACTIVITY OVER NWRN MS AND EVENTUALLY N
   CNTRL/NRN AL.  THESE STORMS WILL TRAVEL SEWD ALONG THE
   BOUNDARY/INSTABILITY GRADIENT. GIVEN SUFFICIENTLY STRONG FLOW ALOFT
   AND DEEP LAYER SHEAR...A NEW WW FOR WIND AND HAIL COULD BE NEEDED IF
   THE SYSTEM STRENGTHENS FURTHER AND PERSISTS.
   
   ..JEWELL.. 04/20/2011
   
   
   ATTN...WFO...BMX...HUN...MEG...JAN...
   
   LAT...LON   33279089 34229020 34518915 34328763 33978696 33378691
               32798763 32798823 33028933 33079008 33279089