MESOSCALE DISCUSSION 0380
   NWS STORM PREDICTION CENTER NORMAN OK
   0136 AM CDT WED APR 03 2013
   
   AREAS AFFECTED...PORTIONS S-CENTRAL/SE TX.
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 81...
   
   VALID 030636Z - 030830Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 81
   CONTINUES.
   
   SUMMARY...ISOLATED DAMAGING-WIND THREAT MAY EXIST FROM
   ELEVATED/BOWING PART OF COMPLEX AS IT MOVES EWD ALONG AND S OF I-10
   TOWARD HOU AREA.  THREAT APPEARS TOO MRGL/CONDITIONAL ATTM FOR
   ADDITIONAL WW.  MEANWHILE..THOUGH TRAILING PART OF COMPLEX HAS
   WEAKENED...ISOLATED SVR WIND/HAIL THREAT PERSISTS OVER CORRIDOR FROM
   MCMULLEN COUNTY EWD TO COASTLINE BETWEEN LAVACA-NUECES COUNTIES.
   
   DISCUSSION...SFC MESOANALYSIS SHOWED OUTFLOW BOUNDARY -- FROM
   COMPLEX DISCUSSED IN SPC MESOSCALE DISCUSSION 379 -- EXTENDING FROM
   JUST OFFSHORE GLS WSWWD OVER SHELF WATERS TO NEAR RKP...MOVING
   SLOWLY SWWD.  PRIMARY PORTION OF MCS IS NE OF WW...N OF THAT
   BOUNDARY...AND MOVING EWD 40-45 KT ACROSS AREA FROM VCT TO I-10
   CORRIDOR.  SFC AIR MASS S OF OUTFLOW BOUNDARY WILL REMAIN
   SUBSTANTIALLY MORE UNSTABLE THAN THAT TO ITS N.  ACCORDINGLY
   MODIFIED FCST SOUNDINGS SUGGEST DEEP LAYER OF NEARLY SATURATED
   THERMODYNAMIC PROFILE WITH MUCAPE RANGING FROM AROUND 500 J/KG ALONG
   I-10 TO 1500 J/KG NEAR BOUNDARY.  DEPTH OF NLYS IN HGX VWP INDICATE
   ROUGHLY 1 KM DEEP STABLE LAYER...WHICH SHOULD BECOME MORE SHALLOW
   WITH SWWD EXTENT.  WLY EFFECTIVE-SHEAR VECTORS WITH 45-50 KT
   MAGNITUDE ARE EVIDENT IN AVAILABLE VWP AND FCST SOUNDINGS. GIVEN
   THESE FACTORS...OCNL STG-DAMAGING GUSTS...BUT LARGELY BELOW 50-KT
   SVR CRITERIA...MAY PENETRATE STABLE OUTFLOW LAYER TO SFC.  
   
   FARTHER SW...ANY CONVECTION THAT CAN ACCESS BOUNDARY-LAYER AIR MASS
   FROM WW EWD TO COAST WILL ENCOUNTER MLCAPE 1000-1500 J/KG....AMIDST
   50-60 KT EFFECTIVE SHEAR MAGNITUDE.  WHILE THESE FACTORS ARE
   FAVORABLE...TSTM COVERAGE IS IN DOUBT.  STRONGER EML-RELATED MLCINH
   IS APPARENT WITH SWWD EXTENT...WHICH APPEARS TO BE SUPPRESSING
   ADDITIONAL DEVELOPMENT ALONG TRAILING COLD-POOL EDGE.  THAT OUTFLOW
   SHOULD BECOME MORE SHALLOW WITH TIME...LIMITING LIFT.
   
   ..EDWARDS.. 04/03/2013
   
   
   ATTN...WFO...LCH...HGX...CRP...EWX...
   
   LAT...LON   28199876 28529778 29199693 29909684 30079410 29869398
               29679405 29419465 29309475 28849537 28459621 28309643
               27939697 27809710 27769843 28199876