Mesoscale Discussion 1187
   NWS Storm Prediction Center Norman OK
   0910 PM CDT Fri Jun 21 2019

   Areas affected...portions of southern Texas

   Concerning...Severe potential...Watch unlikely 

   Valid 220210Z - 220415Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Isolated damaging wind gusts and perhaps some severe hail
   may accompany an MCS approaching from Mexico. Given the localized
   nature of the threat, a WW issuance is not expected at this time.

   DISCUSSION...Convection has recently grown upscale into a small MCS
   in Coahuila Mexico within the past two hours, with a bowing
   structure recently noted via KFDX radar. Outflow has recently
   outpaced the MCS, though the convection remains vigorous. While
   deep-layer shear is weak across the area, strong instability
   remains, with 3500+ J/kg MLCAPE noted. Low-level shear is expected
   to continue increasing given the development of a nocturnal LLJ
   across the area. The stronger low-level shear and aforementioned
   instability may assist the MCS in remaining organized and perhaps
   persisting into portions of southern Texas. As nocturnal cooling
   will help stratify the boundary layer with time, damaging wind gusts
   will continue to be the primary threat with this MCS. Severe hail
   also cannot be ruled out given the relatively steep 700-500 mb lapse
   rates (over 8 C/km via the latest RAP forecast soundings).

   Given the somewhat localized nature of the severe threat, a WW
   issuance is not anticipated at this time.

   ..Squitieri/Kerr.. 06/22/2019

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

   ATTN...WFO...CRP...EWX...

   LAT...LON   28100005 28610045 29110065 29460106 29720097 29720003
               29599923 29139896 28709898 28169939 27919986 28100005