027
FXUS64 KLUB 271752
AFDLUB

Area Forecast Discussion
National Weather Service Lubbock TX
1252 PM CDT Sat Apr 27 2024

...New AVIATION...

.SHORT TERM...
(Today and tonight)
Issued at 354 AM CDT Sat Apr 27 2024

Surface observations at 3 AM show a gradual westward retreat of the
dryline to a position roughly along a line from Jayton to Paducah to
Childress, with dewpoints progged to rise into the 60s across most
of the eastern Rolling Plains through mid-morning. Water vapor and
nighttime composite imagery also depict a zone of impressive
positive 850mb theta-e advection along the nose of a strong
nocturnal LLJ which is captured quite well by real-time RAP analysis
as well as most hi-res models. Satellite imagery also highlights a
broad fetch of midlevel moisture over El Paso quickly shifting
eastward ahead of the core of an upper level low over the Four
Corners region. Isolated to scattered elevated thunderstorms are
expected to develop along the nose of the LLJ early this morning
over southeastern portions of the Caprock and southern portions of
the Rolling Plains and spread northeastward through the remainder of
the morning. Accelerating height falls ahead of the upper low have
resulted in fairly steep midlevel lapse rates over this region with
elevated parcel MUCAPEs potentially exceeding 3000 J/kg. This ample
instability along with respectable effective shear magnitudes
near 40 kt will support a threat for large hail over the Rolling
Plains with this morning convection. Early-day convection will
exit our area by midday as strengthening surface southwesterlies
associated with a deepening surface low over the OK Panhandle
shove the dryline further to our east. While solidly breezy on the
Caprock, wind speeds look to remain just below advisory criteria.
Dry downsloping flow will result in elevated to critical fire
danger across most of the Caprock, and a Red Flag Warning is in
effect for the SW TX Panhandle and western South Plains this
afternoon and evening.

There is still significant uncertainty in this evening`s forecast
given the difficulty of pinpointing the eventual location of the
dryline. Most solutions still place the dryline to the east of
our forecast area this evening, though it is worth noting some
models bring the dryline into the eastern Rolling Plains as surface
flow backs across the Big Country and western North Texas. If the
dryline does indeed retreat into the eastern Rolling Plains and
SE TX Panhandle, thunderstorm development would be possible along
the dryline circulation itself, or later in the evening as the
Pacific front overtakes the dryline. To account for this
uncertainty, have maintained mentionable PoPs across most of the
Rolling Plains this afternoon through late this evening. All
severe hazards would be possible if these storms do materialize,
with large hail being the primary threat. On the other hand, if
the dryline does remain to our east, dry and breezy conditions
will continue area-wide. Dry westerly breezes and slightly cooler
conditions are then expected tonight in the wake of the Pacific
front.

&&

.LONG TERM...
(Sunday through Friday)
Issued at 354 AM CDT Sat Apr 27 2024

Pleasant end to the weekend in the wake of today`s system. A lee low
will develop through the afternoon across northeast New Mexico with
light westerly surface winds and sunny skies giving way to highs in
the mid 70s to lower 80s. The low will skirt across the northern
portions of the forecast area Monday morning with the passing a
passing shortwave trough aloft. A very shallow and weak surface
front will shift winds briefly to the northwest but quickly return
to the west southwest through the day. Thus, temperatures are not
expected to be affected and highs will warm to above normal in the
80s. Mostly zonal westerly flow will return aloft Tuesday with
downsloping surface winds and very warm temperatures in the lower
90s. A dryline will setup diagonally from southwest to northeast
across the central portions of the forecast area. Breezy southwest
winds and dry conditions may lead to elevated to critical fire
weather concerns west of the dryline, mostly across the far
southwest Texas Panhandle and western South Plains. East of the
dryline dewpoints will range in the 40s to 50s, with southerly
surface winds. The better axis of moisture and instability will be
positioned across the eastern Rolling Plains where an isolated
thunderstorm is possible during the afternoon and early evening
hours.

Southwesterly flow returns aloft through the remainder of the work
week with a positively tilted trough axis digging into the Pacific
Northwest. Warm downsloping southwesterly surface winds will give way
to very warm temperatures again on Wednesday in the upper 80s to
lower 90s. The dryline will once again setup over the area, but
there are some inconsistencies with the exact location of the
boundary. Depending on the postilion of the dryline, showers and
thunderstorms are likely to return east of the boundary with a few
strong to even severe storms possible. The surface low will
translate eastward Wednesday night into Thursday with a very weak
surface cold front to swing southward. However, the latest 00z runs
have the front washing out in the southern Texas Panhandle as
another lee low develops in northeast New Mexico. Daytime
temperatures Thursday will heavily depend on how far south the weak
front pushes. If the front moves farther south through the area,
temperatures will remain near normal in the 80s. However, if the
front washes out farther north then warm downsloping southwesterly
surface winds will give way to the potential for temperatures
warming into the 90s. Discrepancies creep up in the pattern aloft
heading into Friday as models vary in evolution of the positively
tilted trough axis over the Upper Rockies. All in all, there appears
to be a 700mb cold front that dives south through the area, but the
timing and strength rely heavily on the system aloft. Cooler and
cloudy conditions are likely Friday, along with potentially the
return of post frontal precipitation across the area into the
weekend. Stay tuned for forecast updates with forecast trends likely
to change due to model disagreement towards the end of next week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1232 PM CDT Sat Apr 27 2024

VFR conditions are expected to prevail through this TAF period.
Thunderstorms near KCDS at the beginning of the TAF period will
move away from KCDS bringing an end to any lightning potential by
1830z. Additional thunderstorm development is possible this
afternoon and evening however confidence on this directly
impacting KCDS remains too low at this time to include a
prevailing mention. Surface winds will also remain gusty at all
three sites through around sunset. Winds will veer behind a
Pacific cold front this evening and overnight but winds should
remain below 15 kts.

&&

.FIRE WEATHER...
Issued at 354 AM CDT Sat Apr 27 2024

Near-critical to critical fire weather conditions are expected this
afternoon and evening across the western South Plains and the far
southwestern TX Panhandle. Here, sustained southwest winds of 20 to
30 mph with gusts to 40 mph along with minimum RH values in the low
teens will support RFTI values of 4 to 6. A Red Flag Warning is in
effect for this area from 1 PM until 8 PM CDT.

Further east across the I-27 corridor, winds will be slightly weaker
with sustained speeds of 15 to 25 mph and gusts to 40 mph. ERC
values are also slightly lower in this area given recent rainfall,
higher fuel moisture, and more advanced spring green-up. Given these
factors and RFTI values of 2 to 4, have opted for a Rangeland Fire
Danger statement for the I-27 corridor, which is in effect from 1 PM
until 8 PM CDT.

Isolated to scattered thunderstorms are possible this morning across
most of the Rolling Plains, with thunderstorm chances returning
this evening across the eastern Rolling Plains. West winds of 10 to
15 mph will continue tonight with RH recovery generally above 50
percent.

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 8 PM CDT this evening for TXZ021-022-027-
028-033-034-039.

&&

$$

SHORT TERM...30
LONG TERM....11
AVIATION...58