MESOSCALE DISCUSSION 0589
   NWS STORM PREDICTION CENTER NORMAN OK
   0625 PM CDT SUN APR 26 2009
   
   AREAS AFFECTED...PORTIONS W-CENTRAL/SW TX.
   
   CONCERNING...TORNADO WATCH 193...
   
   VALID 262325Z - 270130Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 193 CONTINUES.
   
   CONTINUE WW.  TWO COUNTIES HAVE BEEN MOVED INTO THIS WW FROM WW 192
   -- HASKELL AND THROCKMORTON.  NEW/REPLACEMENT WW MAY BE REQUIRED
   BEFORE SCHEDULED 03Z EXPIRATION.
   
   COMPLEX OF SVR TSTMS OVER I-10 INCLUDES SUPERCELL THAT HAS PRODUCED
   TORNADO WITHIN PAST HOUR IN W-CENTRAL CROCKETT COUNTY...ALONG WITH
   VERY LARGE/DESTRUCTIVE HAIL OVER 4 INCHES DIAMETER NEAR SHEFFIELD
   TX.  OTHER SVR TSTMS WILL CONTINUE TO MOVE ENEWD TO NEWD FROM
   PORTIONS STERLING/MITCHELL COUNTIES...INTO ENVIRONMENT CHARACTERIZED
   BY INCREASING LOW LEVEL SHEAR WITH EWD EXTENT...E.G. 0-1 KM SRH
   GENERALLY 200-350 J/KG BASED ON AVAILABLE VWP DATA AND MODIFIED RUC
   SOUNDINGS.  INFLOW REGION ACROSS AREAS OF SW TX AND EDWARDS PLATEAU
   WILL REMAIN CHARACTERIZED BY BACKED SFC WINDS ENHANCING
   STORM-RELATIVE INFLOW...AND ELONGATING LOW LEVEL HODOGRAPHS DESPITE
   SOME KINEMATIC WEAKNESSES APPARENT IN 1-3 KM LAYER.  SFC DEW POINTS
   MID 60S F ARE ANALYZED UPSTREAM FROM THIS ACTIVITY...ALONG WITH PW
   ABOVE 1.5 INCH...CONTRIBUTING TO POTENTIAL FOR HEAVY-PRECIP STORM
   CHARACTER WITH RAIN RATES ABOVE 3 INCHES/HOUR IN ADDITION TO MLCAPE
   AROUND 2000 J/KG.
   
   DEEP-LAYER SHEAR AND LARGE SCALE ASCENT ALOFT EACH WEAKENS WITH SWD
   EXTENT...WHILE MLCINH WEAKENS.  THESE TRENDS WILL
   CONTINUE...HOWEVER...OROGRAPHICALLY FORCED INITIATION OF SVR TSTMS
   IS POSSIBLE ACROSS OVER MEX MOUNTAINS OF NRN COAHUILA.  ANY SUCH
   DEVELOPMENT WOULD MOVE SLOWLY EWD TOWARD RIO GRANDE AND INTO
   STRONGER CAPPING.  VIS IMAGERY INDICATES TCU AND BRIEFLY GLACIATED
   CB OVER THAT AREA.  WILL CONTINUE TO MONITOR...BUT PRIND ANY SUCH
   ACTIVITY WILL REMAIN IN MEX FOR SEVERAL HOURS.  GREATER CONCERN FOR
   ACTIVITY MOVING OUT OF WW IS WITH I-10 ACTIVITY TURNING TOWARD
   JCT-ECU AREA.
   
   ..EDWARDS.. 04/26/2009
   
   
   ATTN...WFO...FWD...EWX...SJT...LUB...MAF...
   
   LAT...LON   29850232 30570239 32120179 32810115 33359907 32189903
               31809933 31399958 30259963 29480016 28260026 28530038
               29190078 29590128 29760140 29770174 29850232