000
FXUS64 KLUB 250911
AFDLUB

Area Forecast Discussion
National Weather Service Lubbock TX
411 AM CDT Thu Apr 25 2024

...New SHORT TERM, LONG TERM, FIRE WEATHER...

.SHORT TERM...
(Today and tonight)
Issued at 410 AM CDT Thu Apr 25 2024

Current satellite midlevel water vapor imagery shows the upper
trough over southern Cali this morning with moist southwesterly flow
bringing in a plume of high clouds across the area. At the surface,
low clouds have begun to develop across the Texas Panhandle and will
filter southward through the early morning hours. Southeasterly
surface flow will also usher in low clouds from the south, which
will fill in a stratus deck across the area by morning. A
combination of these low and high clouds are expected to linger
through much of the morning hours before clearing from west to east.
A lee low will develop across eastern Colorado today, with a dryline
extending southward across West Texas. Most of the models have the
dryline positioned from north to south along the I-27 corridor (give
or take about a 30 mile buffer east or west). Low 60s dewpoints east
of the dryline will give way to plenty of low level moisture.
Instability will be present during the afternoon hours with MLCAPE
values in excess of 2000-2500 J/kg. Winds aloft will still be on the
weaker side as the upper jet doesn`t approach the area until the
evening hours, thus effective bulk shear values will reside around
30-40 knots. One of the biggest caveats to thunderstorm development
this afternoon is the cloud cover. Several models have the clouds
lingering through most of the afternoon with limited daytime
heating and too strong of convective inhibition. If clouds clear
and convective temperatures can be reached along or east of the
dryline in the afternoon hours tomorrow, a severe storm capable of
very large hail, damaging winds and a tornado cannot be ruled
out. Uncertainty remains high and therefore PoPs were trimmed to
slight chance across mostly the far southeast Texas Panhandle and
northern Rolling Plains where the environment may be able to
overcome the capping inversion with just in time daytime heating.

The threat for severe weather increases around sunset as the right
entrance region of the upper jet passes over the forecast area and
the dryline sharpens. Instability values increase with MLCAPE values
approaching 3000 J/kg as a surge of 850mb theta-e enters the Rolling
Plains. In addition, the low level jet will begin to increase as
well with effective bulk shear values in excess of 60-70 knots. An
isolated supercell or two may develop initially along the dryline in
the late evening hours (~10-11pm) with very large hail, damaging
wind gusts and a tornado or two possible. The Pacific front will be
racing eastward late this evening and therefore any isolated storms
will rapidly grow upscale and linear with the main threat becoming
damaging wind gusts. The setting sun and loss of daytime heating
will also lead to storms becoming elevated and the potential for
tornadoes diminishing. However, a spin up along the line of storms
cannot be completely ruled out with the presence of the cranking low
level jet and slight backing of the southerly surface winds. Storms
will quickly move eastward with the Pacific front as storm motions
are around 50 to 60 knots. Thus any thunderstorm chances will be out
of the Rolling Plains by the early morning hours tomorrow.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 410 AM CDT Thu Apr 25 2024

Relatively zonal flow aloft will prevail Friday as the upper level low
over the Central Plains continues to lift to the northeast while an
secondary upper level low tracks into the Four Corners region.
This will allow pleasant warm and quiet weather conditions Friday with
high temperatures in the upper 70s to mid 80s under clear skies. The
upper level low across the Four Corners region will begin to track
eastward through the early morning hours Saturday allowing the surface
low across the TX/OK Panhandles to amplify, tightening the gradient,
which may lead to wind advisory level southwesterly winds around 30 to
35 mph and patchy blowing dust across areas on the Caprock Saturday.
The dry-line will also make its return Saturday morning, however; given
strong southwesterly winds through the day we can expect the dry-line
to remain fixated across our far eastern column of counties. Regardless
of the ensembles hinting at the possibility of showers and
thunderstorms developing along the dry-line Saturday afternoon; lack of
moisture return, lingering cloud cover, and instability aloft projected
farther east may prohibit convective initiation.

The upper level low will quickly eject to the northeast by Sunday
morning swinging a cold front through the forecast area during the
early morning hours on Sunday. This will shift winds out of the
northwest where they will remain breezy throughout the day. Sadly this
front will not do too much in the way of temperatures with highs in the
70s and 80s expected. Flow aloft will become more zonal by Sunday
evening as upper level ridging begins to build back into the region
with quiet and dry weather expected for the beginning of next week.
Ensembles are continuing to hint at our next disturbance in the flow
aloft next Wednesday. A lot of this will vary upon how much moisture
return we will see across the forecast area Tuesday and Wednesday as
surface winds shift out of the south. Nonetheless will continue with
NBM slight chance PoPs for the time being, given the vast amount of
uncertainty with the evolution of this system.

&&

.AVIATION...
(06Z TAFS)
Issued at 1240 AM CDT Thu Apr 25 2024

Low clouds will move in again tonight at all three TAF sites with
most likely MVFR ceilings, but brief IFR ceilings may occur.
Clouds will clear through the afternoon with the return of VFR
sky conditions. Winds will increase through the day with 15 to 25
knot southerly surface winds through the afternoon and evening
hours. There is a small chance for thunderstorms to develop late
tomorrow night near LBB, but confidence was too low on exact
location at this time. The storms may develop just east of the TAF
site and then are expected to continue moving quickly eastward.

&&

.FIRE WEATHER...
Issued at 410 AM CDT Thu Apr 25 2024

Critical fire weather conditions are possible this afternoon across
the far southwest Texas Panhandle and western South Plains. Very dry
conditions will persist west of the dryline with minimum relative
humidity values dipping into the single digits. Southwest surface
winds will increase this afternoon to around 20 to 30 mph with gusts
up to 40 mph possible with the approaching upper trough and
strengthening lee low across eastern Colorado. Clearing clouds will
give way to temperatures warming quite nicely across this area of
concern with highs in the mid to upper 80s.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 1 PM this afternoon to 10 PM CDT this
evening for TXZ021-022-027-028-033-034-039.

&&

$$

SHORT TERM...11
LONG TERM....12
AVIATION...11