656
FXUS64 KLUB 200534
AFDLUB

Area Forecast Discussion
National Weather Service Lubbock TX
1234 AM CDT Sat Jul 20 2024

...New AVIATION...

.SHORT TERM...
(This evening through Saturday)
Issued at 248 PM CDT Fri Jul 19 2024

Weak N-NW flow aloft continued to play host to a few ill-defined
impulses stretching from the South Plains to Colorado. Visible
satellite showed an uptick in mid-level clouds and a few showers
across the far southeast TX Panhandle early this afternoon which
coincides well with a N-S convergence axis from 850-700 mb and a
pocket of higher PWATs around 1.4 inches. Since models are not
keying on this subtle ascent well at all, opted to give satellite
trends more merit with a 10 PoP thunder mention in our NE counties
for a few more hours. Farther west, surface-based instability is
ramping up in our SW Panhandle counties where cumulus fields are
consolidating. This area shows slightly better potential for
spotty storms through the evening, although the main show is
expected to be overnight and mainly to our north as an MCS spreads
southeast from CO and eventually runs out of steam south of I40
after midnight. This decaying theme appears tied to a sharp
dropoff in mid-level lapse rates from NW-SE which is handled well
by most CAMs. Highest PoPs overnight (40%) remain relegated to our
northernmost counties with some 20% extending as far south as
Lubbock during the pre-dawn hours for a potential outflow boundary.

Precip chances during the day tomorrow will hinge on a potential
outflow boundary late tonight and how far south this feature stalls
during the morning. CAMs are more bullish with this outflow and
generally push it south of our CWA resulting in lackluster daytime
precip chances. This scenario is in stark contrast to the coarser
resolution guidance which remains our choice for now given low
confidence in the behavior of tonight`s outflow. Otherwise, high
temps were culled a bit from the NBM given the more unsettled/wetter
theme and increased clouds.

&&

.LONG TERM...
(Saturday night through next Thursday)
Issued at 248 PM CDT Fri Jul 19 2024

By 0Z Sunday, the general synoptic pattern present in the short term
period-- a ridge over the Desert Southwest and troughing over the
eastern half of the country-- stays in place into early next week. A
shortwave trough over the northern Great Plains should develop into
an upper-level low on Sunday, keeping the forecast area in moderate
northwesterly flow aloft Sunday night into Monday. Upper flow turns
meridional beginning midweek as the trough moves east and becomes
increasingly positively-tilted.

A generally favorable environment for precipitation persists through
early next week. Upsloping afternoon winds and lingering boundaries
from prior convection suggest multiple foci for thunderstorm
development: the high terrain of New Mexico, from which storms may
propagate into the FA under NW flow, or areas of weak convergence
along remnant boundaries. A couple of weak shortwaves passing
through the area on Sunday and Monday may also help initiate/sustain
convection. As a result, NBM`s widespread chance/likely PoPs have
been kept for Sunday evening into Monday afternoon.

Precip chances taper off later in the week as steering flow becomes
less favorable and 500mb heights rise Thursday under the east side
of the ridge. Expect below average temperatures through early next
week, then temps warming to near average beginning Wednesday.

&&

.AVIATION...
(06Z TAFS)
Issued at 1229 AM CDT Sat Jul 20 2024

Low confidence forecast with several possible windows for
convection at all TAF sites. Overnight, a complex of scattered TS
along a line from AMA to CVN at 05z will drift slowly
southeastward. This activity is expected to gradually decrease in
coverage overall, but there is a low chance of TS overnight at all
terminals. Highest confidence is at CDS where VCTS mention was
added, but no TS mention was included at either LBB or PVW
overnight given the uncertainty. In addition to convective
potential, outflow will result in a shift to northwest winds
overnight.

Winds return to a predominantly southerly direction on Saturday
morning with renewed convective chances developing by mid-
afternoon. Very high uncertainty regarding exactly where afternoon
storms develop, but at least scattered coverage seems probable
with impacts possible during the afternoon/evening at all
terminals. Outside of convection, VFR is expected to prevail at
all sites.

&&

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

$$

SHORT TERM...93
LONG TERM....99
AVIATION...30