ZCZC SPCSWOMCD ALL
ACUS11 KWNS 180635 
SPC MCD 180635 
TXZ000-OKZ000-180900-

Mesoscale Discussion 0664
NWS Storm Prediction Center Norman OK
0135 AM CDT Sat May 18 2019

Areas affected...west-central into north Texas...southern Oklahoma

Concerning...Severe potential...Watch likely 

Valid 180635Z - 180900Z

Probability of Watch Issuance...95 percent

SUMMARY...Severe storms are expected to develop and organize across
west Texas, and rapidly develop northeastward across northwest Texas
into southern Oklahoma. Significant damaging winds and a few
tornadoes are possible.

DISCUSSION...Substantial moisture and strong instability are already
in place across much of TX, with persistent south/southwest 850 mb
low-level jet of 40 kt. This will maintain an unstable and
relatively uncapped air mass in place as height falls with the upper
trough occur throughout the night. While isolated severe storms
currently exist over parts of southwest TX, a marked increase in
development is expected in the 07-09Z time frame, with upscale
organization likely. A few supercells are possible given substantial
veering winds with height and strong instability with steep lapse
rates aloft, although there is a veer-back signal above 700 mb.
Therefore, a mixed storm mode is expected, with a threat of both
widespread damaging winds with bows and with a few embedded/brief
tornadoes. This threat will accelerate northeast into southern OK by
12-15Z, and toward the Dallas/Ft. Worth area shortly thereafter with
a continued severe threat to the east.

..Jewell/Bunting.. 05/18/2019

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

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

LAT...LON   32500176 33350063 33939965 34359888 34979819 35089764
            34699713 34119711 33569723 32959746 32109823 31139962
            31060027 31120089 31570160 31960193 32160199 32500176 

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