MESOSCALE DISCUSSION 0786
   NWS STORM PREDICTION CENTER NORMAN OK
   0610 PM CDT THU MAY 23 2013

   AREAS AFFECTED...TX PANHANDLE/NORTHWEST TX AND FAR WESTERN OK

   CONCERNING...TORNADO WATCH 213...

   VALID 232310Z - 240045Z

   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 213 CONTINUES.

   SUMMARY...TORNADO WATCH 213 CONTINUES...WITH A LESSENING TORNADO
   POTENTIAL ASIDE FROM LARGE HAIL AND WHAT SHOULD BE AN INCREASING
   DAMAGING WIND THREAT ESPECIALLY ACROSS THE LOW ROLLING PLAINS OF TX.
   PORTIONS OF WATCHES 213 AND/OR 214 MAY WARRANT A SPATIAL WATCH
   EXTENSION.

   DISCUSSION...SUPERCELL MERGERS APPEAR TO ALREADY BE LEADING TO
   UPSCALE CONVECTIVE GROWTH ACROSS THE NORTHWEST TX LOW ROLLING
   PLAINS...ROUGHLY 50 MILES TO THE NORTH OF I-20 AND
   SWEETWATER/ABILENE AREAS AS OF 2245Z. ALTHOUGH SOME TORNADO THREAT
   MAY CONTINUE...MAINLY WITH SEMI-DISCRETE/INITIAL-MERGER
   DEVELOPMENT...A MORE MODEST SHEAR ENVIRONMENT WITH SOUTHWARD EXTENT
   AND CONTINUED CELL MERGERS WILL LIKELY CONTINUE TO LEAD TO
   UPSCALE/MCS DEVELOPMENT. ACCORDINGLY...AT LEAST A LOCALIZED 
   DAMAGING WIND THREAT SHOULD INCREASE WITH A CONTINUED
   SOUTH-SOUTHEASTWARD PROPAGATION/GRADUAL ACCELERATION TOWARD/ACROSS
   I-20...INCLUDING THE SNYDER/SWEETWATER/ABILENE AREAS. SOME INCREASE
   IN SOUTHEASTERLY WINDS BETWEEN 1-2 KM AT WSR-88D VWP DATA FROM DYESS
   AFB/SAN ANGELO OVER THE PAST HOUR OR TWO SUPPORT THE NOTION OF
   INCREASING STORM-RELATIVE INFLOW/SUSTAINED PROPAGATION.

   FARTHER NORTHWEST...A MERGER BETWEEN WEST-NORTHWESTWARD MOVING
   OUTFLOW AND FRONTAL BOUNDARY HAS CONTRIBUTED TO ADDITIONAL
   DEVELOPMENT JUST NORTH-NORTHWEST OF THE AMARILLO AREA AS OF 2245Z. A
   SPECIAL 21Z OBSERVED SOUNDING SAMPLED A VERY STEEP ELEVATED LAPSE
   RATE PROFILE WITH AN ADJUSTED 2500+ J/KG OF MLCAPE WITHIN A VEERING
   WIND PROFILE /45-50 KT OF EFFECTIVE SHEAR/. LARGE HAIL WILL THE
   PRIMARY HAZARD...ALTHOUGH SOME TORNADO THREAT MAY EXIST AS WELL
   SHOULD RIGHT-MOVING SUPERCELLS DEVELOP/PERSIST ALBEIT WITHIN A
   SOMEWHAT COOLER/OUTFLOW INFLUENCED ENVIRONMENT.

   ..GUYER.. 05/23/2013


   ATTN...WFO...FWD...OUN...SJT...LUB...AMA...MAF...

   LAT...LON   35550245 35800077 33899978 33289881 31799921 32790198
               35550245