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218
FXUS64 KLUB 020820
AFDLUB

Area Forecast Discussion
National Weather Service Lubbock TX
320 AM CDT Thu May 2 2024

...New SHORT TERM, LONG TERM...

.SHORT TERM...
-- Changed Discussion --
(Today and tonight)
Issued at 313 AM CDT Thu May 2 2024

A welcome respite from severe storms awaits much of the forecast
area today with the exception found roughly along and east of the
Highway 83 corridor where a cold front and dryline intersection
later today could fuel a few severe storms. Until then, we`ll be
contending with moist E-SE upslope flow this morning thanks to a
large mesohigh in the wake of an MCS still churning over N TX as of
2 AM. This upslope flow will maintain some stratus over the region
until a cold front drives south later this morning and scours this
away. Clearing may struggle in our eastern column of counties where
deeper moisture within a theta-E axis ahead of a dryline may serve
as an obstacle to the front and effectively slow its progress. Any
low clouds here should still scatter out by midday while allowing
for MLCAPEs of 1500-2500 J/kg with minimal CIN. Sufficient deep
layer shear of 30-35 knots within weakly cyclonic SW flow should
help storms remain organized with some supercells once again on the
table. However, there is more uncertainty than yesterday with storm
development as some recent hi-res models are accelerating FROPA
through most of the Rolling Plains by the afternoon which would shut
the door on our 20-30 PoPs. This scenario will be revisited through
the day and adjusted accordingly.

As the cold front stalls this evening to our south, N winds will
veer E and tug richer moisture westward onto the Caprock. This
upslope regime looks favorable for stratus development overnight and
potentially some fog. Various soundings exhibit stratus depths
increasing to 1000-2000 feet thick which could be enough for drizzle
at times, while higher aloft there exists a bit of ECAPE for thunder
should any elevated ascent materialize. Kept PoPs very low after
midnight and favoring our NE zones where moist isentropic ascent is
a bit more evident than elsewhere.
-- End Changed Discussion --

&&

.LONG TERM...
-- Changed Discussion --
(Friday through Wednesday)
Issued at 313 AM CDT Thu May 2 2024

Post-frontal easterly upslope flow will continue through the day on
Friday which will result in a continued increase in low level
moisture. However, guidance is still not in agreement regarding
the magnitude of this moisture return, with some models
considerably more agressive in bringing a notable theta-e ridge
northward into our area by early afternoon. There is also a
growing signal of deepening surface troughing over eastern NM
providing a dry downslope component near the TX/NM state line on
Friday afternoon, and should this occur, a diffuse dryline may set
up somewhere over the forecast area during the afternoon hours on
Friday. A subset of synoptic models as well as some hi-res
solutions do depict scattered thunderstorms developing along this
feature Friday afternoon and evening, though capping and weak
forcing aloft may limit coverage. Nevertheless, the signal is
strong enough to maintain PoPs Friday afternoon and evening with
highest chances along and east of I-27 with a severe storm or two
not out of the question either.

Attention then turns to the potential for more widespread showers
and storms Saturday into Sunday with locally heavy rainfall also
looking like a good bet over portions of the region. Early
Saturday, initially west-southwesterly flow aloft will strengthen
and back to a more southwesterly direction as a well-defined
mid/upper level disturbance transits overhead. At the surface, a
cold front will pass southward through the region early in the day
before washing out over the southern South Plains or Permian
Basin region during the afternoon. The presence of the remnant
frontal boundary combined with robust low level upslope flow and
increasing large-scale forcing for ascent is expected to result in
the development of fairly widespread showers and thunderstorms
late Saturday through early Sunday. Periods of heavy rainfall
appear possible particularly late Saturday night off the Caprock
where rich deep layer moisture (PWATs near 200 percent of normal)
intersect with more coherent forcing associated with the difluent
region of a southern stream jet streak. Overall, ensemble
consensus suggests rainfall totals in excess of one inch will be
possible over most of the Rolling Plains and SE TX Panhandle, with
lesser amounts on the Caprock.

Showers and storms will decrease in coverage from west to east
throughout the day on Sunday, although PoPs do remain elevated off
the Caprock for most of the day where moist upslope flow persists
for longest. A fairly potent upper low will then pass eastward
over the Intermountain West on Monday, but the track of this low
still appears to be too far north to support widespread additional
storm chances locally, except for the SE TX Panhandle and eastern
Rolling Plains where a a couple of storms may be possible Monday
afternoon before moisture exits eastward. Instead, most of the
region is expected to see warm, dry, and breezy conditions return
on Monday and persist through the middle of next week.
-- End Changed Discussion --

&&

.AVIATION...
(06Z TAFS)
Issued at 1230 AM CDT Thu May 2 2024

MVFR stratus will continue to expand overnight on moist E-SE
upslope winds, with CDS more likely to see this lower to IFR
before daybreak. A FROPA and N wind shift later this morning
will scour these clouds away and restore VFR, although this could
prove a tougher task at CDS where moisture will linger. Not
impossible that a few TS could redevelop near CDS during the
afternoon along the front.

&&

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

$$

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