MESOSCALE DISCUSSION 0492
   NWS STORM PREDICTION CENTER NORMAN OK
   0412 AM CDT THU APR 29 2004
   
   AREAS AFFECTED...PORTIONS SE TX/SW LA
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 290912Z - 291145Z
   
   TSTMS MAY DEVELOP THROUGH ABOUT 12Z OVER MID/UPPER TX COASTAL
   PLAIN...IN WAKE OF DISSIPATING MCS.  VERTICAL WIND PROFILES WILL BE
   FAVORABLE FOR BOTH SUPERCELL AND BOW ECHO MODES OF CONVECTION.
   
   TWO MCVS ARE EVIDENT IN LONG LOOPS OF REGIONAL REFLECTIVITY DATA. 
   THESE ARE MOVING NEWD ACROSS CENTRAL/SE TX...ONE BETWEEN HOU-CLL AND
   THE OTHER JUST S TPL AS OF 9Z. TSTM POTENTIAL WILL INCREASE AS
   MESO-BETA SCALE SUBSIDENT ZONE -- IN WAKE OF THESE VORTICES --
   PASSES NEWD AND YIELDS TO LARGE SCALE DPVA/ASCENT JUST AHEAD OF
   UPPER LEVEL TROUGH.
   
   MOST FAVORED AREA FOR DEVELOPMENT WILL BE ALONG AND N OF OUTFLOW
   BOUNDARY...AMIDST LOW LEVEL WAA PROFILE.  SFC MESOANALYSIS SHOWS
   OUTFLOW BOUNDARY FROM INVOF CLL SWD TO WHARTON/COLORADO COUNTY
   LINE...TO JUST N VCT....ACROSS GOLIAD/LIVE OAK COUNTIES TO ABOUT 20
   S COT. BOUNDARY SHOULD REMAIN QUASISTATIONARY S OF I-10 AND
   DECELERATE FARTHER N AS PARENT MCS CONTINUES TO DISSIPATE.  EXPECT
   COLD POOL NW OF BOUNDARY TO BECOME GRADUALLY MORE SHALLOW...WITH
   DESTABILIZATION OVERHEAD BECOMING FAVORABLE FOR TSTMS OVER NEXT FEW
   HOURS. MODIFIED RUC SOUNDINGS INDICATE CINH DECREASING THROUGH 12Z
   AND MUCAPE INCREASING INTO 500-1000 J/KG RANGE.  35-45 KT LLJ
   EVIDENT IN REGIONAL PROFILER/VWP DATA WILL PROVIDE FAVORABLY MOIST
   STORM-RELATIVE INFLOW JUST ABOVE SFC.  ALSO...50-60 KT MIDLEVEL FLOW
   OBSERVED ACROSS PORTIONS S-CENTRAL TX APPEARS UNDERFORECAST BY
   MODELS AND WILL ENHANCE DEEP-LAYER SHEAR.
   
   ..EDWARDS.. 04/29/2004
   
   
   ATTN...WFO...LCH...HGX...CRP...EWX...
   
   29479531 28589707 28459796 29139789 30249732 30909598
   30769499 30249458