Lorenzo, Texas Weather Forecast Discussion

946
FXUS64 KLUB 081119
AFDLUB
Area Forecast Discussion
National Weather Service Lubbock TX
619 AM CDT Mon Sep 8 2025
...New AVIATION...
.KEY MESSAGES...
Updated at 615 AM CDT Mon Sep 8 2025
- A few thunderstorms will be possible across the far
   southeastern Texas Panhandle and Rolling Plains this evening
   into tonight.
- Dry and hot weather is forecast Tuesday through Friday.
- Low storm chances return this upcoming weekend.
&&
.SHORT TERM...
(Today and tonight)
Issued at 1224 AM CDT Mon Sep 8 2025
03Z upper air analysis depicts an amplifying subtropical ridge over
the Intermountain West, with a closed, longwave trough continuing to
shift eastward over the northeastern U.S. and Canada towards the
North Atlantic. The mid-level center of the subtropical ridge
continues to rotate over Baja California Sur, with the 250 mb
anticyclone remaining tilted from the mid-level center, but it
should become aligned by mid-day Monday ahead of a bifurcation in
the jet stream farther northwest over the far northeastern Pacific
Ocean. A near-zonal jet streak was observed by the 08/00Z
objectively analyzed UA charts, with about 50 kt of 250 mb flow
advecting over the CWA that weakens and veers northwestward in the
mid-levels to around 20 kt. The large-scale subsidence layer had
caused earlier thunderstorms near the NM state line and the far
southwestern TX PH to collapse quickly, and fair weather is expected
area-wide through Monday afternoon. Subtropical ridging will
continue to amplify and slowly slosh eastward over the next 24
hours, which will orient the steering flow towards the northwest.
At the surface, the quasi-stationary front previously located to the
west of the CWA has undergone its final stage of frontolysis, with a
transition into a diffuse trough based on METAR and WTM data. An
expansive surface high was located in the Upper Midwest, with a
broad fetch of moist, southeasterly flow encompassing the CWA and
dewpoints in the lower 60s area-wide. Return flow will remain intact
throughout the short-term period, with surface winds veering
poleward by Monday afternoon in response to the leeward pressure
falls associated with cyclogenesis along the higher terrain of NM
and eastern CO. Stratus will develop once again during the pre- and
post-dawn hours Monday due to the low-level jet nearing 20 kt at the
top of the decoupled boundary-layer, which will have reached its
saturation point. The stratus deck will delay the onset of diabatic
heating, but after it mixes out, temperatures are forecast to spike
into the middle-upper 80s area-wide due to the net increase in
geopotential heights aloft.
PoPs generated by the NBM, which were mainly delineated across the
far southern TX PH, were removed through Monday afternoon, as
subsidence will continue to advect over W TX and prevent parcels
from reaching the LFC despite the hotter temperatures. Although a
surface-based cu field will bubble in concert with peak heating, any
congested cu/Tcu will succumb to the effects of dry air entrainment,
especially given the lack of low-level convergence. However, as the
evening arrives, a loosely-organized cluster of storms propagating
southeastward out of the eastern TX PH/western OK and along the
thickness gradient may clip portions of the far southeastern TX PH
and Rolling Plains. Therefore, a broad area of slight chance PoPs
(i.e., 20-percent) were introduced across the aforementioned locales
between 09/00-06Z, or 7 PM CDT through 1 AM CDT Tuesday. The system
will be decaying rapidly as it nears the CWA due to the increasing
subsidence aloft and loss of daytime heating, but a few cells may be
sustained through the evening and early nighttime hours Monday. The
severe weather risk is low, but a rogue gust or two near 50 mph
cannot be ruled out during the early evening hours across the far
southeastern TX PH, especially as outflow(s) surge ahead of the
collapsing cells. Storm potential across the Rolling Plains will end
by 09/06Z Tuesday, with benign weather to follow and similar low
temperatures compared to the previous morning.
Sincavage
&&
.LONG TERM...
(Tuesday through Sunday)
Issued at 1224 AM CDT Mon Sep 8 2025
Drier and hotter weather is forecast Tuesday through the end of the
week. At the beginning of the period, a wavy, split-flow pattern
will be evolving across the western U.S., as a train of well-defined
PV anomalies propagate over the northern waters of the Pacific Ocean
and into far northwestern Canada. This will allow a mature cyclone,
which is currently centered over 41 N/133 W, or due west of the
CA/OR state line, to progress eastward into the Great Basin and
deepen by Wednesday. The subtropical ridge will shift over the
southern Great Plains in response to the western U.S. troughing,
with strong subsidence forecast to nix storm development while the
increase in geopotential heights boosts high temperatures into the
middle 90s area-wide each day Tuesday through Friday. Return flow
will also remain intact throughout the remainder of the week, as
leeward pressure falls are maintained by the daily cyclogenesis
generated from the intensifying cross-barrier flow.
By the end of the week and into next weekend, global NWP guidance
continues to indicate an anticyclonically-breaking wave event to
occur over the higher latitudes. The periodicity of waves that break
anticyclonically are on the order of 1-2 weeks, which results in a
typical and slow, eastward progression of the closed lows that spawn
within the southern tranche of the split-flow due to the positive
momentum fluxes that cause the primary jet stream to translate
poleward. (Sometimes, the closed lows can become cut-off, but
guidance is also bifurcated on this scenario.) There is still a fair
amount of spread among the global NWP guidance on the amplitude and
position of the southern-stream troughing and how long it takes for
it to open. Regardless, there is increasing confidence in at least
broadly cyclonic flow to advect over W TX by next weekend. The NBM
is catching onto this, with low PoPs reflected in the official
forecast for next weekend and into early next week.
Sincavage
&&
.AVIATION...
(12Z TAFS)
Issued at 615 AM CDT Mon Sep 8 2025
A broken deck of MVFR stratus will expand in coverage over the
region through the next few hours, but confidence is low regarding
timing of impacts to the terminals. At this time, it appears that
LBB has the best potential of seeing a period of persistent MVFR
CIGs that continues through most of the morning, with a shorter
duration of MVFR CIGs looking more likely at PVW and CDS. There
is also a nonzero chance that CIGs fall to IFR this morning,
especially at LBB, but confidence in this occurring is low. Expect
conditions to improve around midday with VFR expected to return
to all TAF sites this afternoon through tonight.
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...09
LONG TERM....09
AVIATION...30

NWS LUB Office Area Forecast Discussion