MESOSCALE DISCUSSION 0646
   NWS STORM PREDICTION CENTER NORMAN OK
   0334 PM CDT THU APR 30 2009
   
   AREAS AFFECTED...EASTERN/SOUTHERN AR AND SOUTHEAST MO/NORTHERN LA
   INTO NORTHWEST MS AND WESTERN PORTIONS OF TN/KY
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 302034Z - 302200Z
   
   POTENTIAL FOR DAMAGING WINDS/HAIL SHOULD DEVELOP THROUGH LATE
   AFTERNOON ACROSS PORTIONS OF EASTERN/SOUTHERN AR AND PERHAPS
   SOUTHEAST MO/NORTHERN LA INTO NORTHWEST MS AND THE WESTERN PORTIONS
   OF TN/KY. GIVEN THE EXPECTED MARGINAL/ISOLATED NATURE OF THE
   RISK...THE NEED FOR A WATCH IS UNCLEAR.
   
   SATELLITE IMAGERY REFLECTS MCV CROSSING NORTHERN AR AT MID
   AFTERNOON. A GRADUAL UPSWING IN CONVECTIVE COVERAGE/INTENSITY HAS
   BEEN NOTED ON THE EASTERN PERIPHERY OF THIS MCV...AND THIS SAME
   TREND SHOULD CONTINUE THROUGH LATE AFTERNOON AS THE DOWNSTREAM
   AIRMASS DESTABILIZES TOWARD/ACROSS THE MISSISSIPPI RIVER. MODEST
   CLOUD BREAKS/HEATING AND SURFACE DEWPOINTS MAINLY IN THE
   LOWER/MIDDLE 60S ARE SUPPORTING AS MUCH AS 500 J/KG OF SBCAPE
   IMMEDIATELY AHEAD OF THE EASTERN AR DEVELOPMENT...ALTHOUGH A
   RESERVOIR OF STRONGER INSTABILITY /1000-2000 J PER KG/ RESIDES
   ACROSS SOUTHERN AR/NORTHERN LA. SOMEWHAT ENHANCED MID LEVEL FLOW IN
   ASSOCIATION WITH THE MCV WILL FAVOR SUFFICIENTLY ORGANIZED/MAINLY
   MULTICELLULAR CONVECTION CAPABLE OF DAMAGING WINDS/MARGINALLY SEVERE
   HAIL. WILL MONITOR FOR A POSSIBLE WATCH.
   
   ..GUYER.. 04/30/2009
   
   
   ATTN...WFO...OHX...PAH...MEG...JAN...LZK...SHV...
   
   LAT...LON   36459085 37158867 36168802 33708943 32499083 32549307
               33489307 34329185 36459085