Unrated tornado, Aspermont Arpt, Texas, April 22, 2019

Area Forecast Discussion
National Weather Service Lubbock TX
648 PM CDT Mon Apr 22 2019

.AVIATION...
Periods of showers and thunderstorms are expected to impact all
three terminals through the next 12 hours or so. Aside from the
precipitation and possibly strong winds accompanying the storms,
low ceilings are expected to develop and persist well into Tuesday
morning. Flight conditions should be mainly IFR to MVFR, but
localized LIFR conditions are possible. Ceilings will be slow to
improve on Tuesday, and may not return to VFR.

&&

.PREV DISCUSSION... /issued 237 PM CDT Mon Apr 22 2019/

DISCUSSION...
Surface observations at 2 PM revealed a stationary front stretching
from south of Hobbs to Lamesa to northwest of Haskell. Winds north
of this front have slowly veered more easterly and some northward
displacement to this front is likely, particularly tonight once moisture
advection amplifies in response to a decent SSE low level jet. Thus
far, insolation and instability have been curbed under dense mid
and high clouds, but some pockets of thinning clouds and warmer
temps are evident in Andrews County. Along with weak moisture
convergence pooling along the nearby front, this clearing may
help spur isolated or scattered surface based convection later
this afternoon that could easily spread NE into at least our far
southern row of counties. Favorable wind shear and MLCAPE would
support supercell structures (mainly near the front), but the
bigger story should transition to larger rounds of elevated
convection this evening and overnight as PWATs rise to over 1 inch
across most of the region. With 850-700 mb winds holding from the
south and southeast all night downstream of a mesolow in
southeast NM, the stage appears set for multiple rounds of
training convection generally just north of the stationary/pseudo-
warm front. This large window of favorable lift and PWATs could
easily deposit 1-2" of rain over much of the area, but a widespread
flooding risk does not appear in the cards with this event so we
have refrained from a flood watch for now. PoPs were boosted to
100% overnight from the eastern South Plains northeast to the SE
Panhandle where ensembles, CAMS, and deterministic models are in
great agreement for measurable rainfall. Lulls in precip are likely
at times overnight before another slug of deeper lift arrives
between midnight and daybreak with the arrival of a shortwave
trough currently exiting Arizona.

Following additional rounds of elevated convection Tuesday morning,
the aforementioned mesolow and front will be shunted south ahead
of surface high pressure and PWATs falling to half of their peak
amounts. This should focus afternoon PoPs mainly in our far S-SE
zones outside of the earlier antecedent rains, but if this front
is delayed any then the threat for flooding would certainly
amplify given earlier antecedent rains. Aloft, the left exit
region of a high level jet max should provide further background
ascent with some heavy rains again possible due to storm motions
paralleling the front. Current indications are that the cold front
should be departing our CWA by mid/late afternoon when the window
for more robust convection opens, so the severe threat certainly
looks less favorable tomorrow in our area. PoPs were gradually
scaled lower from N-S in the afternoon and continuing through
tomorrow night as saturated depths erode ahead of dry ridging and
northerly flow. However, the edge of a SW-NE oriented moisture
plume aloft and on/off rain chances should remain largely intact
from our far southern zones into the Rolling Plains as an upper
low tracks eastward across the Permian Basin on Wednesday.
Soundings show only modest instability by this time, so showers
and/or stratiform rain should be the main mode of precip on Wed
before the column dries out on Thu. Dry and much milder
conditions close out the end to week and rally into the weekend
under deep westerly flow with some prospects for precip by early
next week as a dryline ensues ahead of a Canadian front and
progressive upper trough.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&

33

Hazardous Weather Outlook...UPDATED
National Weather Service Lubbock TX
643 PM CDT Mon Apr 22 2019

TXZ021>044-231000-
Parmer-Castro-Swisher-Briscoe-Hall-Childress-Bailey-Lamb-Hale-
Floyd-Motley-Cottle-Cochran-Hockley-Lubbock-Crosby-Dickens-King-
Yoakum-Terry-Lynn-Garza-Kent-Stonewall-
643 PM CDT Mon Apr 22 2019

This Hazardous Weather Outlook is for the South Plains, Rolling
Plains and the far Southern Texas Panhandle.

.DAY ONE...Tonight

Scattered to numerous thunderstorms are expected to impact much of
the region tonight. Some of these storms may become severe with
large hail to around golf ball size and wind gusts near 60 mph.
Also, very heavy rain and localized flooding will be possible
through the night.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

The heavy rainfall threat will continue through Tuesday before
tapering off Tuesday night. Rain will finally end from west to
east late Wednesday across the region as the storm system
responsible for the precipitation moves east of the region.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be requested.

Special Weather Statement
National Weather Service Lubbock TX
738 PM CDT Mon Apr 22 2019

TXZ044-230100-
Stonewall TX-
738 PM CDT Mon Apr 22 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN KING AND STONEWALL
COUNTIES UNTIL 800 PM CDT...

At 737 PM CDT, Doppler radar was tracking a strong thunderstorm 10
miles south of Aspermont, moving north at 30 mph.

Nickel size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Aspermont, Old Glory, and Swenson.

A Severe Thunderstorm Watch remains in effect until 200 AM CDT for
northwestern Texas.

LAT...LON 3296 10018 3296 10042 3340 10036 3334 9999
      3317 9999
TIME...MOT...LOC 0037Z 199DEG 25KT 3300 10027