MESOSCALE DISCUSSION 0349
   NWS STORM PREDICTION CENTER NORMAN OK
   0244 PM CDT TUE MAR 31 2009
   
   AREAS AFFECTED...PARTS OF CNTRL/SRN MS INTO SRN LA
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 97...
   
   VALID 311944Z - 312115Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 97
   CONTINUES.
   
   THROUGH 22Z...EXPECT THE GREATEST SEVERE WEATHER THREAT TO EXIST
   OVER SRN PORTION OF WW 97 AREA...MAINLY S OF THE MS/LA STATE LINE.
   
   RECENT TRENDS IN REGIONAL RADAR IMAGERY INDICATE INTENSIFYING STORMS
   ALONG TRAILING EXTENSION OF DECAYED MCS OUTFLOW BOUNDARY FROM EAST
   FELICIANA PARISH SWWD TO ACADIA PARISH WITH A GENERAL STORM MOTION
   OF 250/30-40 KT.  WATER VAPOR IMAGERY SUGGESTS THAT THIS INCREASE IN
   STORMS MAY BE IN PART ASSOCIATED WITH THE APPROACH OF A LOW
   AMPLITUDE IMPULSE EMBEDDED WITHIN THE SUBTROPICAL AIRSTREAM.
   
   IMMEDIATE INFLOW AIR MASS IS WARM AND QUITE MOIST WITH MLCAPE OF
   1000-1500 J/KG...INCREASING TO AROUND 2000 J/KG OVER SERN LA /PER
   18Z LIX SOUNDING/.  WHILE LOW-LEVEL WIND FIELDS HAVE VEERED AND
   WEAKENED SINCE THIS MORNING...RATHER STRONG MID AND HIGH-LEVEL FLOW
   COINCIDENT WITH SUBTROPICAL JET AXIS IS RESULTING IN SUFFICIENT
   DEEP-LAYER SHEAR FOR ORGANIZED STORMS INCLUDING SUPERCELLS AND/OR
   BOWS.  HAIL AND DAMAGING WINDS WILL REMAIN THE PRIMARY SEVERE
   WEATHER THREATS WITH THE MOST INTENSE STORMS.
   
   FARTHER N OVER MS...REMNANT OUTFLOW ASSOCIATED WITH DECAYED MCS IS
   NOW NEARING THE AL BORDER NEAR OR N OF MEI.  THIS BOUNDARY APPEARS
   TO NOW HAVE MERGED WITH THE LEADING EDGE OF CONVECTIVE OUTFLOW WHICH
   HAS EMANATED FROM PERSISTENT ELEVATED TSTM ACTIVITY TO THE E.  THE
   NET RESULT IS THAT AIR MASS OVER NRN PART OF WW AREA HAS BECOME MUCH
   LESS SUITABLE FOR SURFACE-BASED STORMS.  SEVERE WEATHER STILL
   REMAINS POSSIBLE ACROSS SRN MS /GENERALLY S OF I-20/...BUT AS
   MENTIONED ABOVE...THE GREATEST THREAT MAY REMAIN S OF THE MS/LA
   STATE LINE.
   
   ..MEAD.. 03/31/2009
   
   
   ATTN...WFO...BMX...MOB...JAN...LIX...LCH...SHV...
   
   LAT...LON   29729416 31469369 32229044 33288968 33098821 31718834
               28668898 29049343 29729416