459
FXUS64 KLUB 271727
AFDLUB

Area Forecast Discussion
National Weather Service Lubbock TX
1227 PM CDT Thu Jun 27 2024

...New AVIATION...

.SHORT TERM...
(Today and tonight)
Issued at 334 AM CDT Thu Jun 27 2024

The center of an upper-level ridge will expand eastward today but be
shunted a bit south thanks to a quick moving low across the Northern
Rockies. This will knock heights down a bit over the forecast area
today which when combined with our slightly cooler start to the day,
will allow afternoon high temperatures to be near to slightly cooler
than yesterday. High temperatures will range from the mid 90s across
the far southern Texas Panhandle (where rainfall occurred yesterday)
to near 105 degrees across the southern Rolling Plains. Winds will
be out of the south today and increase this afternoon with sustained
wind speeds of 15-20 mph and gusts up to 30 mph. While these winds
won`t be southeasterly like yesterday they will still help to keep
surface moisture in place across the forecast area hence muggy
conditions are expected once again. The combination of heat and
humidity will lead to heat index values up to 109 degrees across the
eastern Rolling Plains and far southeastern Texas Panhandle hence
another Heat Advisory has been issued for this area from 1 pm until
8 pm today. If surface dewpoints fail to mix out once again this
afternoon then the Heat Advisory may need to be expanded westward.
The area will also be drier today as a capping inversion is expected
to remain in place across the forecast area which will prevent
widespread thunderstorm development. However, isolated thunderstorm
development may be possible across the northern Rolling Plains and
far southeast Texas Panhandle this afternoon as any left over
boundary from the morning convection could serve as a focus and
allow the cap to be overcome. If that occurs, modestly steep mid-
level lapse rates will allow for MLCAPE values of around 2000 J/Kg
with effective shear values around 25 kts which would allow for at
least organized clusters of storms to develop. The main hazard with
any storm that develops would be the potential for damaging straight
line winds. With the loss of daytime heating, thunderstorms will
diminish leading to a quiet but warm night across the forecast area
with low temperatures in the 70s to lower 80s.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 334 AM CDT Thu Jun 27 2024

The upper level ridge over the region will begin to flatten Friday
as an upper level trough over northern CONUS scoots through portions
of the High Plains. This will allow flow aloft to become more zonal
where it will remain relatively weak through the weekend. Sadly the
upper level ridge and associated high pressure will begin to rebuild
rather quickly over portions of North Texas by early next week where
it will stick around through the mid-week before it begins its
eastward track into portions of the southeastern US.

Surface winds on Friday will shift out of the southwest becoming
breezy across the Caprock as the pressure gradient tightens as a lee
cyclone digs into portions of the northern Texas Panhandle. These
breezy southwest winds will help boost temperatures into the triple
digits once again Friday. Given we saw high temperatures in the low
to mid 100s on the Caprock and up to 108 off the Caprock on
Wednesday, we may see even warmer temperatures than that Friday
given thickness values will be slightly higher. Knowing this,
decided to nudge temperatures warmer Friday with the NBM 75th
percentile. As the ridge begins to flatten through the weekend we
will see a slight reprieve from these triple digit temperatures,
besides a few locations off the Caprock who may see localized triple
digit temperatures. Sadly, this will be a rather small and quick
cool down with temperatures in the mid to upper 90s still expected
this weekend. As the ridge build back over, temperatures will begin
to warm once again with upper 90s and triple digits in the forecast
through the remainder of the long term period, BOOO...!

One minor change was made to the Friday precipitation forecast where
an isolated (10%) mention of PoPs was added for portions of the
South Plains and far south-central Texas Panhandle. Given low to mid
level moisture is still expected to remain in place we may see a few
thunderstorms develop off the higher terrain in eastern New Mexico
as a subtle perturbation in the flow aloft tracks to our northeast.
If thunderstorms develop and make it into our area, flow aloft looks
to remain weak out of the southwest, storms would likely remain sub-
severe given the lack of instability in place. Better chances for
precipitation arrive this weekend, however a few caveats remain that
could potentially limit thunderstorm development/activity. The first
caveat being the positioning of the upper level high pressure
system, this will dictate where the bulk of the moisture will reside
as it wraps around its center. As it stands, latest model guidance
suggest that most of the moisture will remain well to our north and
west. Secondly, forecast soundings suggest a decent capping
inversion in place over the region with subsidence at the surface
and aloft which could limit thunderstorm development. Lastly, our
best source of lift looks to come from a very weak front tracking
southward from the Texas Panhandle Friday night. Latest guidance has
this boundary stalling just north of the FA which would allow for a
drier forecast to unfold. If these caveats are able to be overcome,
we could see some strong to sub-severe thunderstorms develop this
weekend. The forecast will begin to dry out through the beginning
of next week as the upper level ridge builds back over. However,
the future is looking bright for increased precipitation chances
by midweek as the upper level ridge shifts eastward and an upper
level trough digs through the Intermountain West.

&&

.AVIATION...
(18Z TAFS)
Issued at 1227 PM CDT Thu Jun 27 2024

VFR expected for the next 24 hours. Breezy, southerly winds are
expected for KLBB and KPVW through the evening, with gusts up to
25 kts possible. Winds will diminish after dark. Check density
altitude.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT this evening for TXZ026-032-038-044.

&&

$$

SHORT TERM...58
LONG TERM....12
AVIATION...09