MESOSCALE DISCUSSION 0535
   NWS STORM PREDICTION CENTER NORMAN OK
   0238 AM CDT SAT MAY 01 2004
   
   AREAS AFFECTED...SRN AR/NRN LA
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 010738Z - 010815Z
   
   LONG-LIVED BOW ECHO HAS JUST MOVED INTO EXTREME SWRN AR MOVING EWD
   AT 40 KTS.  KSHV 88D DEPICTS AN OUTFLOW BOUNDARY...EMANATING FROM
   DECAYING LINEAR MCS OVER CNTRL AR...HAD MOVED INTO SRN AR AND IS
   LINKED UP WITH THE BOW.  EXTRAPOLATION HAS THE FEATURE MOVING OUT OF
   WW 139 AROUND 0800 UTC...IF IT HOLDS TOGETHER. THERE ARE SOME
   INDICATIONS THAT IT MAY WEAKEN.  MESOANALYSIS DEPICTS THAT INFLOW
   AIR IS NOT PARTICULARLY UNSTABLE WITH FEED OF MOST UNSTABLE PARCELS
   ARCING NWWD WEST OF THE SABINE RVR VLY INTO MCS OVER ECNTRL TX.  IF
   THE INTEGRITY OF THE FORWARD PROPAGATING SYSTEM IS MAINTAINED
   THROUGH 0800 UTC...ANOTHER WW MAY BE REQUIRED DOWNSTREAM ALONG THE
   LA/AR BORDER FOR A DAMAGING WIND POTENTIAL.
   
   MEANWHILE...TSTMS HAVE BEEN INCREASING OVER ECNTRL TX IN THE WARM
   ADVECTION REGIME AHEAD OF MCS. PRIND THAT TSTMS WILL CONTINUE TO
   DEVELOP EWD INTO WRN LA THE NEXT SEVERAL HOURS.  WHILE DEEP LAYER
   SHEAR IS MARGINAL FOR SUSTAINED ORGANIZED CONVECTION... AVAILABILITY
   OF 2500 J/KG MUCAPE AND UNIDIRECTIONAL WIND FLOW IN THE CAPE BEARING
   LAYER MAY AUGMENT POTENTIAL FOR BOWS/LEWPS WITH DAMAGING WIND GUSTS.
   
   ..RACY.. 05/01/2004
   
   
   ATTN...WFO...JAN...LZK...LCH...SHV...
   
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