MESOSCALE DISCUSSION 0165
   NWS STORM PREDICTION CENTER NORMAN OK
   0240 PM CST FRI FEB 27 2009
   
   AREAS AFFECTED...AR
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 37...
   
   VALID 272040Z - 272145Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 37
   CONTINUES.
   
   REMAINING VALID PORTION OF WW 37 WILL BE ALLOWED TO EXPIRE...BUT A
   MARGINAL SEVERE THREAT MAY PERSIST INTO EARLY EVENING.
   
   A COLD INTRUSION CONTINUES TO ADVANCE SOUTHEAST OF THE SOUTH CENTRAL
   PLAINS AND OZARK PLATEAU...WITH THE LEADING SURFACE FRONT NOW
   CURVING ACROSS NORTHWEST MISSISSIPPI THROUGH THE LOUISIANA/ARKANSAS
   BORDER AREA INTO THE TEXAS HILL COUNTRY.  HOWEVER...A MOIST RETURN
   FLOW OFF THE GULF OF MEXICO CONTINUES TO OVERRUN THE FRONT....AHEAD
   OF A VIGOROUS SHORT WAVE TROUGH NOW DIGGING TO THE LEE OF THE
   CENTRAL ROCKIES.  THIS IS CONTRIBUTING TO WEAK TO MODERATE
   INSTABILITY AND RENEWED CONVECTIVE DEVELOPMENT TO THE NORTH OF A
   CAPPING WARM MID-LEVEL LAYER...WHICH MAY YET DRIFT A BIT FARTHER TO
   THE NORTH/NORTHEAST ACROSS ARKANSAS THROUGH THE REMAINDER OF THE
   AFTERNOON.  DESTABILIZATION MAY REMAIN SUFFICIENT FOR STRONG STORM
   DEVELOPMENT IN THE PRESENCE OF FAVORABLE CLOUD BEARING LAYER SHEAR
   FOR UPDRAFT ROTATION.  BUT...THE RISK FOR LARGE HAIL APPEARS TO BE
   THE PRIMARY SEVERE THREAT WITH CONVECTION BASED ABOVE THE DEEPENING
   FRONTAL INVERSION ACROSS PARTS OF WEST CENTRAL INTO SOUTH CENTRAL
   ARKANSAS.
   
   ..KERR.. 02/27/2009
   
   
   ATTN...WFO...MEG...LZK...TSA...
   
   LAT...LON   35739399 35749288 35199146 34589091 33619128 33689265
               34659451 35739399