Mesoscale Discussion 2044
   NWS Storm Prediction Center Norman OK
   0117 AM CST Sat Dec 18 2021

   Areas affected...Central/East TX

   Concerning...Severe potential...Watch unlikely 

   Valid 180717Z - 180915Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Increasing thunderstorm coverage is expected across
   central TX over the next several hours. A few storms may become
   strong enough to produce hail and/or damaging wind gusts.

   DISCUSSION...Recent surface analysis places a cold front from
   southeast OK southwestward back through north-central TX and then
   more westward across the TX Big Country into the Permian Basin.
   Northerly wind gusts behind this front are around 20-30 kt, and the
   expectation is that the front will continue surging southeastward
   throughout the night. Warm sector ahead of the front from central TX
   through the Arklatex is characterized by temperatures in the upper
   60s to low 70s and dewpoints in the low to mid 60s. These conditions
   beneath relatively steep mid-level lapse rates (around 7-7.5 degrees
   C per km from 700 to 500 mb) are resulting in a moderately buoyant
   airmass with MLCAPE around 1000-1500 J/kg. In addition to this
   buoyancy, persistent southwesterly flow aloft (mainly above 700 mb)
   stretches across the warm sector and mesoanalysis estimates
   effective bulk shear around 40-45 kt. 

   Satellite imagery depicts a shortwave trough embedded within this
   southwesterly flow moving through central Mexico, and the lift
   associated with shortwave augmented by ascent attendant to the cold
   front is forecast to result in increased thunderstorm coverage
   across central TX tonight. Given the environmental conditions
   described above, a few of these storms may become strong enough to
   produce hail and/or damaging wind gusts. Weak low-level flow should
   keep the tornado potential low and limited overall severe coverage
   will likely preclude the need for a watch.

   ..Mosier/Grams.. 12/18/2021

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

   ATTN...WFO...SHV...HGX...FWD...EWX...SJT...

   LAT...LON   30419925 31499861 32489730 32749669 32709598 32419543
               31649516 30989549 29629715 29419746 29189790 29079828
               29099877 29279914 30419925