MESOSCALE DISCUSSION 0435
   NWS STORM PREDICTION CENTER NORMAN OK
   0421 AM CDT FRI APR 15 2011
   
   AREAS AFFECTED...NRN LA...SERN AR...CNTRL AND NRN MS...WRN/MIDDLE TN
   
   CONCERNING...TORNADO WATCH 139...
   
   VALID 150921Z - 151045Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 139 CONTINUES.
   
   A NEW WW MAY BECOME NECESSARY EAST OF WW 139 WITHIN THE NEXT HOUR OR
   TWO.
   
   INFLOW INTO ONGOING STRONG/SEVERE MESOSCALE CONVECTIVE SYSTEM IS
   STRONGEST ON IT SOUTHERN FLANK...NOW SPREADING ACROSS SOUTHERN
   ARKANSAS AND NORTHERN LOUISIANA...WHERE BOUNDARY LAYER MOISTURE
   CHARACTERIZED BY MID/UPPER 60S SURFACE DEW POINTS CONTINUES TO
   SUPPORT MODERATE CAPE AROUND 1000-1500 J/KG.  IN THE PRESENCE OF A
   SHEARED AND STRONG DEEP LAYER MEAN FLOW FIELD...ON THE ORDER OF
   40-50+ KT...THIS SEEMS LIKELY TO MAINTAIN THE STRENGTH OF THE
   CONVECTION THROUGH AND BEYOND DAYBREAK...EVEN AS STRONGEST MID/UPPER
   SUPPORT DEVELOPS NORTHEAST OF THE REGION TOWARD THE LOWER OHIO
   VALLEY.  AS A RESULT THE RISK FOR DAMAGING WIND GUSTS ...PERHAPS
   ISOLATED TORNADOES...SHOULD CONTINUE EASTWARD ACROSS MUCH OF CENTRAL
   MISSISSIPPI THROUGH THE 10-12Z TIME FRAME.
   
   FARTHER NORTH...THE INTENSITY OF THE SQUALL LINE HAS RECENTLY
   DIMINISHED AS IT APPROACHED THE MISSISSIPPI RIVER...BUT BOUNDARY
   LAYER MOISTENING IN A NARROW CORRIDOR AHEAD OF THE ACTIVITY STILL
   MAY PROVIDE POTENTIAL FOR INTENSIFICATION ACROSS PARTS OF WESTERN
   INTO MIDDLE TENNESSEE THROUGH DAYBREAK.
   
   ..KERR.. 04/15/2011
   
   
   ATTN...WFO...OHX...BMX...HUN...PAH...MEG...JAN...SHV...
   
   LAT...LON   32959143 33959087 34529026 35308970 36068952 36538803
               36238697 33038806 32478907 31739018 31439129 31549255
               31949282 32959143