041
FXUS64 KLUB 030554
AFDLUB

Area Forecast Discussion
National Weather Service Lubbock TX
1254 AM CDT Fri May 3 2024

...New AVIATION...

.SHORT TERM...
(This evening through Friday)
Issued at 205 PM CDT Thu May 2 2024

A cold front, oriented in an arcing fashion from southwest to
northeast, has moved through the western portion of the area and is
moving through the northeastern counties as of 2 PM. Meanwhile,
clouds have mostly cleared out ahead of the cold front where there
is relatively rich low-level moisture. Anticipating that a very
gradual low-level moisture gradient in the southern CWA will begin
to tighten through the afternoon into a dryline, and thunderstorms
are favored to develop in the mid to late afternoon. The primary
uncertainty is regarding where the dryline will be when
thunderstorms begin to develop, and where exactly they will develop.
The chance for thunderstorms today is focused on the southeast, but
it is possible that thunderstorms develop just south or east of the
CWA. Regardless, with sufficient low-level moisture in place and
steep lapse rates, MLCAPE will climb to around 1500-2500 J/kg,
possibly slightly higher, in the southeast along with effective
shear values around 40-50 kts. This suggests thunderstorms would
become supercellular, and due to a relatively straight hodograph, a
splitting supercell may occur initially. Very large hail and
damaging winds would be the primary threats. A tornado can`t be
ruled out, but would be more favored south or east of Stonewall
county. Again, this is conditional upon thunderstorms being able to
develop in the CWA and being able to mature enough prior to moving
out of the area. Low-level moisture moves in with upsloping easterly
winds which favors the development of fog in the east and north,
possibly with some drizzle. Can`t entirely rule out some elevated
convection, but there is low confidence in that at this time.

Tomorrow, winds turn southeasterly ahead of another weak shortwave
trough and moisture is brought back in. Mid to upper-level support
for ascent looks rather modest at best, but a dryline is favored to
push east in the mid to late afternoon which may help focus ascent
and develop convection along the boundary. That said, if morning
clouds linger and/or the cap is slightly too strong, then
thunderstorms may struggle to develop. If thunderstorms can develop,
forecast thermodynamic profiles look somewhat similar to today, but
shear looks slightly weaker. Regardless, all hazards would be
possible with hail possibly exceeding 2 inches in diameter. This may
linger into a portion of the evening before weakening due to a loss
of daytime heating.

Vanden Bosch

&&

.LONG TERM...
(Friday night through next Wednesday)
Issued at 205 PM CDT Thu May 2 2024

SUMMARY...A wet and stormy start to the weekend is in store for much
of the area. On top of a low-end threat for severe storms on
Saturday, eastern portions of the area appear favored to receive
localized areas of substantial rainfall through Sunday morning.
After a cooler weekend, warm temperatures look to quickly rebound
next week as moisture exits the region.

DISCUSSION...Model indications continue to suggest strong to severe
storms may develop Saturday along and ahead of an approaching
shortwave disturbance within southwest flow aloft. Placement of a
cold front slated to advance southward through the morning hours,
before eventually stalling out, may ultimately dictate where this
threat will occur. Increasing east-southeasterly sfc flow ahead of
the front should aid in strong moisture return Saturday, allowing
for moderate destabilization by the afternoon hours with modest
daytime heating. Model forecast soundings depict steep mid-level
lapse rates in the presence of aforementioned instability and
adequate deep-layer shear, suggesting large hail and strong winds
would be the primary hazards in strongest storms. It appears
however, that extended periods of heavy rainfall may be the more
prominent element this weekend. Rich theta-e advection to the area
combined with persistent enhanced lift along the remnant boundary
should help to generate widespread showers and storms through Sunday
morning. With anomalously high PWATs over 1.00-1.50" and favorable
large scale ascent expected to be in place, higher rain amounts are
certainly on the table, especially for areas off the Caprock towards
the Big Country. Here, deterministic and ensemble guidance signal
medium to high probabilities (50-80%) for rainfall totals to exceed
1 inch before convection pushes eastward through the day Sunday.

Model guidance agrees a far more pronounced upper low lifts into the
Great Plains on Monday, but will track too far north, generally
leaving moist of the CWA high and dry. Can`t entirely rule out some
stray convection across the far eastern counties Monday afternoon,
but chances are <20% at this time. In this system`s wake, zonal flow
aloft and rising 850mb temps are progged to initiate a warming
trend, with highs in the 80s to low 90s along with breezy winds
through midweek.

Harrel

&&

.AVIATION...
(06Z TAFS)
Issued at 1250 AM CDT Fri May 3 2024

MVFR and IFR conditions are expected to develop at all three
terminals tonight as low stratus fills in. Drizzle is also
possible late tonight and may reduce visibilities to MVFR at
times in addition to lowering ceilings. Thunderstorms are expected
to develop tomorrow afternoon possibally in the vicinity of all
three terminals but will likely be isolated at KLBB and KPVW so
thunderstorm mention has remained omitted from these TAF sites as
well as KCDS. However, chances are higher that KCDS will encounter
thunderstorms in the afternoon tomorrow.

&&

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

$$

SHORT TERM...99
LONG TERM....99
AVIATION...17