MESOSCALE DISCUSSION 0287
   NWS STORM PREDICTION CENTER NORMAN OK
   0759 PM CDT TUE MAR 19 2013
   
   AREAS AFFECTED...CNTRL THROUGH SERN TX
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 56...
   
   VALID 200059Z - 200230Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 56
   CONTINUES.
   
   SUMMARY...TENDENCY SHOULD BE FOR STORMS TO DEVELOP SEWD THROUGH
   CNTRL AND SCNTRL TX THROUGH THE EVENING. SOME OF THE STORMS WILL
   EVOLVE INTO SUPERCELLS WITH A THREAT FOR ISOLATED LARGE HAIL AND
   DAMAGING WIND. SOME POTENTIAL ALSO EXISTS FOR ACTIVITY TO
   CONSOLIDATE INTO A SMALL MCS LATER THIS EVENING.
   
   DISCUSSION...EARLY THIS EVENING A FRONT EXTENDS FROM SWRN LA WWD
   THROUGH SCNTRL TX NEAR AUSTIN AND FARTHER WEST TO SOUTH OF SAN
   ANGELO AND WINK. THIS BOUNDARY HAS BEGUN TO ACCELERATE SWD AS A COLD
   FRONT. THE WARM SECTOR REMAINS MODERATELY UNSTABLE /1000-1500 J/KG
   MLCAPE/ WITH MARGINAL INSTABILITY /AOB 1000 J/KG MUCAPE/ JUST TO THE
   COOL SIDE. EML HAS ADVECTED THROUGH SCNTRL AND S TX RESULTING IN
   STRONG CONVECTIVE INHIBITION. THIS SUGGESTS MOST IF NOT ALL
   THUNDERSTORM DEVELOPMENT WILL REMAIN CONFINED TO ZONE OF DEEPER
   ASCENT NORTH OF THE FRONT AS IT CONTINUES SWD WITH A NET SEWD STORM
   MOTION. THESE STORMS WILL BE ELEVATED...BUT SUFFICIENT EFFECTIVE
   SHEAR EXISTS TO SUPPORT SOME SUPERCELL STRUCTURES. OBSERVATIONS AND
   POINT FORECAST SOUNDINGS INDICATE 15-20F TEMPERATURE-DEWPOINT
   SPREADS IN THE COOLER BOUNDARY LAYER NORTH OF FRONT WHICH MIGHT AID
   COLD POOL FORMATION AND EVENTUAL UPSCALE MCS GROWTH IF A SUFFICIENT
   NUMBER OF STORMS CAN DEVELOP.
   
   ..DIAL.. 03/20/2013
   
   
   ATTN...WFO...HGX...FWD...EWX...SJT...
   
   LAT...LON   31939933 31329732 30719619 29569634 29789781 30549982
               31939933