SPC MD 810
MD 0810 CONCERNING SEVERE THUNDERSTORM WATCH 237... FOR TEXAS BIG BEND INTO PECOS VALLEY



Mesoscale Discussion 0810
NWS Storm Prediction Center Norman OK
0635 PM CDT Wed May 20 2026

Areas affected...Texas Big Bend into Pecos Valley

Concerning...Severe Thunderstorm Watch 237...

Valid 202335Z - 210130Z

The severe weather threat for Severe Thunderstorm Watch 237
continues.

SUMMARY...A small cluster of storms continues to pose some risk for
severe hail and wind, but this potential probably will diminish
while spreading toward the San Angelo vicinity through 8-9 PM CDT.

DISCUSSION...Strongest storms have been maintained on the
northeastern flank of convective outflow slowly propagating off the
higher terrain, in the presence of strongly sheared (due to veering
of winds with height) but weak southwesterly deep-layer mean flow on
the order of 15-20 kt. This is where northeasterly surface winds to
the cool side of a weakening surface front may be enhancing
convergence along the outflow, and low-level warm advection above
the front may be still maximized. However, latest guidance suggests
that this forcing may begin to weaken within the next couple of
hours, resulting in diminishing convective intensities, if an influx
of less unstable updraft does not weaken convection sooner.

..Kerr.. 05/20/2026

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

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

LAT...LON 30620214 31030196 31090081 30320167 30030245 30620214

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


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https://www.spc.noaa.gov/products/md/md0810.html