Hail and Damaging Winds in Texas, May 15, 2018

Area Forecast Discussion
National Weather Service Lubbock TX
338 PM CDT Tue May 15 2018

.DISCUSSION...
The front/outflow has pushed even farther south than previous
indications and has taken the focus for convective initiation
farther south into the northern Permian Basin. North of the
boundary, the airmass across our forecast area has become quite
conditionally unstable, with MLCAPES running about 1500 to 3000
J/kg, the max in buoyancy located in the eastern South Plains and
western Rolling Plains. We also have an interesting situation
aloft, with a jet max moving into southwest Texas, and another
advancing into north-central New Mexico. So far, it appears that
our forecast area may be situated under subtle subsidence between
these two jets, although the subsidence may be replaced by weak
ascent by evening as the shortwave to our west edges closer. The
upshot is that there is still some t-storm potential across much
of the forecast area this afternoon and evening. The cap has
pretty much eroded across the South Plains and we'll watch for any
left-moving storms coming in from the Permian Basin and/or
additional development possible along outflows or possibly
retreating boundary across the western or southern South Plains.
Additionally, t-storms developing along the higher terrain in
northern NM are expected to organize and propagate eastward, then
turning southeast into the strengthening LLJ this evening. There
is a good chance that this activity may clip our northern and
northeast counties this evening.

On Wednesday, east-southeast low-level flow should keep the
dryline backed up near the state line through the day. Shortwave
ridging will be approaching from the west, but it appears that
modest northwest flow immediately downstream of the ridge will
provide some lift across the area and give us another chance at
afternoon and evening t-storms.

Heights will rise on Thursday as the shortwave ridge traverses the
region but low-level southeast flow should maintain moisture
levels and the ridge axis is progged to be east of the forecast
area by late afternoon or early evening which will bring us
another window of t-storm development.

Southwesterly flow aloft amplifies on Friday as the next upper-
level system moves across the Great Basin. Strong heating may
prove sufficient to break the cap late in the day, similar to
Thursday except there may be a stronger shortwave approaching by
peak heating - bringing greater lift and shear. it is still
uncertain how far east the dryline will go Friday, but it may
slide farther east given the stronger wind fields aloft.

With upper troughiness lingering to our west this weekend, this
should maintain the chance of t-storms Saturday and Sunday.
Additionally, a cold front may move into the area and provide a
focus for storms. In fact, on their recent 0 and 12 UTC runs,
both the GFS and ECMWF show quite a bit of QPF across the region
late Sunday/Sunday night as the upper trough lifts northeast over
the region. Of course the progression/location of the front may
play a decisive role in where the best rain chances develop.

&&

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

33

Hazardous Weather Outlook...UPDATED
National Weather Service Lubbock TX
1136 AM CDT Tue May 15 2018

TXZ021>044-160445-
Parmer-Castro-Swisher-Briscoe-Hall-Childress-Bailey-Lamb-Hale-
Floyd-Motley-Cottle-Cochran-Hockley-Lubbock-Crosby-Dickens-King-
Yoakum-Terry-Lynn-Garza-Kent-Stonewall-
1136 AM CDT Tue May 15 2018

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

.DAY ONE...This Afternoon and Tonight

Severe storms are expected to develop this afternoon and
evening, primarily from the South Plains into the Rolling Plains.
Additional severe thunderstorms are possible farther north later
this evening and could affect the southern Panhandle. In addition
to heavy rain and localized flooding, the strongest of storms
could produce wind gusts to 80 mph and hail as large as baseballs.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

An unsettled weather pattern will continue through early next week
with daily chances for strong and severe thunderstorm development.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LUBBOCK TX
1105 AM CDT TUE MAY 15 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0615 PM     TSTM WND DMG     5 NNW TELL              34.44N 100.43W
05/14/2018                   HALL               TX   NWS EMPLOYEE

            DOWNED POWER POLE ALONG WEST SIDE OF FM 658. TIME
            ESTIMATED FROM RADAR.

&&

EVENT NUMBER LUB1800059

LUB