MESOSCALE DISCUSSION 0613
   NWS STORM PREDICTION CENTER NORMAN OK
   0909 PM CDT MON APR 27 2009
   
   AREAS AFFECTED...PORTIONS SWRN/S-CENTRAL LA
   
   CONCERNING...SEVERE POTENTIAL...WATCH NEEDED SOON 
   
   VALID 280209Z - 280245Z
   
   NRN PORTION QUASI-LINEAR MCS HAS INTENSIFIED OVER EXTREME SE
   TX...AND SHOULD CONTINUE TO MOVE EWD OVER PORTIONS SWRN/S-CENTRAL LA
   THROUGH 05Z.  WHILE INSTABILITY SHOULD DIMINISH IN FOREGOING AIR
   MASS WITH TIME...MODIFIED 00Z LCH RAOB INDICATES EFFECTIVE INFLOW
   PARCELS WILL REMAIN SFC-BASED FOR A FEW MORE HOURS.  SELY BOUNDARY
   LAYER WINDS WILL HELP TO MAINTAIN STORM-RELATIVE INFLOW...WHILE
   LIFTING ON LEADING EDGE OF COLD POOL HELPS TO MAINTAIN ASCENT OF
   VERY MOIST SLAB OF INFLOW AIR SUPPORTING MLCAPE AROUND 500-800 J/KG.
    LEWP/QLCS CIRCULATIONS MAY YIELD BRIEF/MRGL TORNADO
   THREAT...HOWEVER GREATER SVR MODE SHOULD BE DAMAGING GUSTS.
   
   ..EDWARDS.. 04/28/2009
   
   
   ATTN...WFO...LCH...SHV...
   
   LAT...LON   29689388 30719359 31299363 31379270 31089194 30169166
               29539153 29589170 29459182 29579203 29599218 29539227
               29569266 29769320 29689388