MESOSCALE DISCUSSION 0845
   NWS STORM PREDICTION CENTER NORMAN OK
   0831 PM CDT SAT MAY 21 2011
   
   AREAS AFFECTED...AR AND VICINITY
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 220131Z - 220300Z
   
   STORMS SHOULD CONTINUE TO INCREASE IN COVERAGE ACROSS SRN AR...AND
   SPREAD NEWD WITH TIME.  WITH ENVIRONMENT SUPPORTIVE OF
   SUPERCELLS/SEVERE POTENTIAL...WW ISSUANCE MAY BECOME NECESSARY.
   
   STORMS CONTINUE TO SLOWLY INCREASE IN COVERAGE AND INTENSITY ACROSS
   SRN AR...ON THE NWRN ARC OF AN OUTFLOW BOUNDARY EXTENDING FROM SRN
   AR SEWD ACROSS NRN LA.  STORMS APPEAR TO BE INITIATING IN A ZONE OF
   WARM ADVECTION NEAR THE BOUNDARY...AND AS LOW-LEVEL JET INCREASES
   THIS EVENING...STORM COVERAGE SHOULD CONTINUE TO INCREASE.
   
   WITH THE BACKGROUND ENVIRONMENT FAVORABLE FOR SUPERCELLS...LARGE
   HAIL AND ISOLATED DAMAGING WINDS WILL BE POSSIBLE WITH STRONGER
   CELLS...AS STORMS SPREAD EWD/NEWD ACROSS AR THIS EVENING.  THIS
   REGION WILL CONTINUE TO BE MONITORED FOR POSSIBLE WW.
   
   ..GOSS.. 05/22/2011
   
   
   ATTN...WFO...MEG...JAN...LZK...SHV...TSA...
   
   LAT...LON   32779204 33189362 33909436 34999473 35629427 35979247
               35849134 34779061 33379151 32779204