ZCZC SPCSWOMCD ALL
ACUS11 KWNS 190100 
SPC MCD 190100 
LAZ000-TXZ000-190200-

Mesoscale Discussion 0680
NWS Storm Prediction Center Norman OK
0800 PM CDT Tue May 18 2021

Areas affected...The Arklatex region

Concerning...Severe Thunderstorm Watch 189...

Valid 190100Z - 190200Z

The severe weather threat for Severe Thunderstorm Watch 189
continues.

SUMMARY...The severe threat continues to decline for most of WW 189,
but an isolated wind/hail threat remains possible for parts of the
Arklatex region through the late evening hours.

DISCUSSION...Lightning and IR trends continue to show a gradual
weakening of the QLCS across central AR, and sub-severe winds
recently reported with the line further support this idea. Diurnal
cooling will continue to diminish MLCAPE through the late evening
hours across much of AR, which will further act to mitigate the
severe potential across much of WW 189. Further south across the
Arklatex region, around 1000 J/kg MLCAPE along with 25-35 knots of
effective bulk shear are noted in RAP mesoanalysis ahead of a
cluster of storms emerging out of central TX. While this cluster has
largely exhibited only loose organization, it is forecast to
propagate into parts of the Arklatex area over the next 1-2 hours.
Although confidence is low, isolated instances of severe wind/hail
will remain possible given the environment.

..Moore.. 05/19/2021

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

ATTN...WFO...SHV...HGX...FWD...

LAT...LON   32259559 32669540 32969487 32999432 32689393 32289391
            31909383 31409424 31329493 31679539 32259559 

NNNN