Mesoscale Discussion 0687
   NWS Storm Prediction Center Norman OK
   0210 PM CDT Wed May 19 2021

   Areas affected...Portions of west and west-central TX

   Concerning...Severe potential...Watch unlikely 

   Valid 191910Z - 192145Z

   Probability of Watch Issuance...20 percent

   SUMMARY...An isolated threat for severe hail and strong/gusty winds
   may develop this afternoon. Watch issuance is unlikely.

   DISCUSSION...Weak low-level upslope flow is occurring early this
   afternoon across parts of west and west-central TX based on recent
   surface observations and area VWPs. Diurnal heating has been fairly
   muted across this region today given persistent mid/high-level cloud
   cover in the wake of an expansive MCS and precipitation shield now
   over coastal TX and the Gulf of Mexico. Still, surface dewpoints
   generally in the low to mid 60s, coupled with steep mid-level lapse
   rates noted on the 12Z MAF sounding, will likely support around
   1000-2000 J/kg of MLCAPE in a fairly narrow corridor through the
   remainder of the afternoon. Modest large-scale ascent associated
   with a weakening upper trough over the southern High Plains should
   encourage at least isolated additional storm development as
   convective inhibition weakens with continued diurnal heating. Storms
   may develop over the higher terrain of the Davis/Glass Mountains,
   with other activity possible along a stalled front extending
   southwest to northeast across west TX. Mid-level west-northwesterly
   flow over this region is expected to remain fairly modest, generally
   30-35 kt or less. Even so, there should be enough deep-layer shear
   for some storm organization, with marginal supercells and small
   clusters possible. Isolated instances of severe hail and
   strong/gusty winds may occur with the more robust cores through the
   rest of the afternoon. The eastward extent of the severe threat
   across west-central TX should remain limited by convective
   overturning from earlier storms. The overall severe threat currently
   appears marginal/isolated, and watch issuance is unlikely.

   ..Gleason/Kerr.. 05/19/2021

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...EWX...SJT...MAF...

   LAT...LON   30380333 31420348 32240254 32500058 32469945 32109916
               31479903 30089979 29200084 29580138 29720187 29730229
               29640273 30070323 30380333