119
FXUS64 KLUB 131720
AFDLUB

Area Forecast Discussion
National Weather Service Lubbock TX
1220 PM CDT Tue Aug 13 2024

...New AVIATION...

.SHORT TERM...
(Today and tonight)
Issued at 224 AM CDT Tue Aug 13 2024

Midlevel water vapor satellite imagery reveals the upper ridge
stretched from West Texas to Louisiana, centered over eastern Texas.
Through the day today the ridge will meander ever so slightly east
and be centered over the Arklatex region. With the movement of the
ridge today, temperatures may be a few degrees cooler than
yesterday. However, warm southwest downsloping winds will give way
to continued above normal temperatures. Triple digit heat remains
likely across the far southern Texas Panhandle and Rolling Plains,
but temperatures will remain below heat advisory criteria. In the
wake of the upper ridge will be a shortwave entering the Desert
Southwest. This will bring weak southwesterly flow aloft across New
Mexico, while West Texas remains under south southeasterly flow
aloft along the western periphery of the ridge. Afternoon and
evening thunderstorms will quickly develop across New Mexico today
and move north northeast. The forecast area is expected to remain
under dry air and subsidence with little to no chances for storms.
Similar to this evening, weak activity may develop along an outflow
boundary late tonight across the far southwest Texas Panhandle and
western South Plains. Given the very dry boundary layer and high
cloud bases, anything that does develop will struggle to precipitate
to the surface. Thus the main threat would be gusty winds. NBM PoPs
of below 10 percent were maintained for this evening given the
possibility of precipitation being very low and contingent on an
outflow from the storms across New Mexico.

Childress broke yet another record yesterday for the warmest low
temperature thanks to increased cloud cover overnight helping to
insolate surface temperatures. The official low yesterday (August
12th) at Childress Airport was 84 degrees, which annihilated the
previous record of 79 degrees (set back in 1936). Thanks to another
mild morning today (August 13th), Childress once again has another
shot at tying or breaking the record for warmest low temperature.
The current forecast low is 77 degrees with the previous record
being 78 degrees (set back in 1937). Another mild night tonight will
give way to continued lows in the upper 60s to 70s.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 224 AM CDT Tue Aug 13 2024

Isolated-to-widely-scattered thunderstorms remain in the forecast
for portions of the Caprock and Rolling Plains on Wednesday into
Thursday. At the beginning of the period, a low-amplitude,
progressive wave pattern will envelope the central and northern half
of the Lower 48, with two well-defined centers of the subtropical
ridge positioned near Baja California and into northern Mexico; and
the other rotating over the northern Gulf of Mexico, the Deep South,
and eastern Texas. A high-level shortwave trough will also emerge
over the central Rocky Mountains and eject into the north-central
Great Plains. Mid-level flow will be significantly dampened compared
to the geometry of the 250 mb jet streak, with the troughing
becoming more-basal overall with southward extent into West Texas.
However, the ejection of the shortwave trough and orthogonal
component to the mean flow aloft will result in lee cyclogenesis
across the western Great Plains, with a surface trough branching
southwestward into the TX PH. The isallobaric response will not be
particularly strong, but breezy, south-southwesterly winds will
develop as the lee cyclone gradually deepens to around 1002 mb in
western Kansas by the afternoon hours.

The CWA will also be positioned within the inflection point of a
barotropic-baroclinic state of the synoptic-scale regime,
maintaining very warm mid-levels as subsidence remains intact from
near-neutral geopotential height tendencies associated with the
basal troughing overhead. This will effectively shunt boundary-layer
mixing heights to around 650 mb with Inverted-V profiles beneath the
LCL. Initial development of isolated thunderstorms is expected by
mid-afternoon across portions of the Caprock Escarpment, mainly to
the west of I-27; however, cold pool mergers and the effects of a
storm motion governed by propagation may result in slow-moving,
multi-cellular lines or clusters before the boundary-layer decouples
and updrafts become detrained following the loss of daytime heating.
PoPs were once again raised from the NBM into the chance category
for areas across the far southwestern TX PH where better low-level
convergence may exist compared to areas farther south into the CWA,
but large-scale surface and low-level convergence should be limited
via weak meso-alpha-scale responses across the southern High Plains
from the dampened amplitude of the troughing within the progressive
wave train and the nearby subtropical ridging.

Heading into Thursday, a longitudinal extension of the center of the
subtropical ridge over Baja California is forecast to branch past
the lee of the southern Rocky Mountains as a well-defined shortwave
trough digs into the Cascade Mountains. A cold front associated with
the downstream shortwave trough should also move southward across
the Great Plains but become quasi-stationary to the north of the
CWA. The net result of this should maintain lee cyclogenesis as the
surface low rotates into northwestern Oklahoma on Thursday morning,
with breezy, southerly winds remaining intact which will keep very
warm low temperatures intact, further adding to heat stress. Low
temperatures for Thursday morning were raised (00Z CONSAll) across
the Rolling Plains, with lows in the lower 80s forecast. Slight
chance PoPs were manually added compared to the dry NBM for portions
of the Caprock and all of the Rolling Plains on Thursday, as the
presence of a pre-frontal surface trough extending southward from
the quasi-stationary front should facilitate enough localized
convergence for isolated thunderstorms. The spatiotemporal extent of
storms should be limited, owing to increasing mid-level subsidence
advecting in from the west and as the 250 mb jet remains over the
central Great Plains; and is why PoPs are confined mainly to the
east and southeast of the HWY-385 corridor. High temperatures will
soar above 100 degrees for most locations across the CWA as vertical
mixing heights ascend approximately 50 mb higher than the previous
day. The potential for storms will also wane quickly after dark.

A dry forecast has been maintained with the potential for oppressive
heat heading into the weekend as global NWP guidance remains in
agreement with an Omega Block developing across North America. High
temperatures in excess of 105 degrees (i.e., achieving Heat Advisory
criteria) area forecast for most of the Rolling Plains this weekend
and into early next week. It is possible that an increase occurs in
the temperatures occur in subsequent forecast cycles as both the
deterministic and ensemble spectra of the global NWP guidance suites
indicate geopotential heights nearing 600 dam by early next week.

Sincavage

&&

.AVIATION...
(18Z TAFS)
Issued at 1215 PM CDT Tue Aug 13 2024

Breezy southerly winds will continue through this evening. Gusts
of 20-25 kts are possible at KLBB and KPVW. VFR will persist.

&&

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

$$

SHORT TERM...11
LONG TERM....09
AVIATION...19