785
FXUS64 KHUN 240218
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
918 PM CDT Tue Apr 23 2024

...New NEAR TERM...

.NEAR TERM...
(Rest of tonight)
Issued at 917 PM CDT Tue Apr 23 2024

Temperatures have dropped into the 55 to 65 degree range at this
hour. Clear skies remain over the area with cloud cover not too
far off to the northwest ahead of an approaching weakening cold
front over northeastern AR and southern KY. Some calm winds can be
seen in observations, especially in typical sheltered valley
locations. However, winds in several locations in northern AL and
southern middle TN are between 5 and 10 mph. Expect these winds to
remain fairly steady and increase a tad through much of tonight,
as the pressure gradient increases as the weakening front pushes
southeast and approaches the area around daybreak. A fairly
substantial mid/high cloud deck will likely build southeast into
the area around 3 AM CDT north of the Tennessee River. Could see a
few showers as this occurs in those areas. Between winds and
cloud cover, expect lows to be a bit warmer than previously
thought, likely dropping only into the 50 to 55 degree range west
of the I-65 corridor. Further southeast, lows may drop a bit lower
into the mid 40s to lower 50s with clear skies holding on longer.
Given expected winds, no fog is expected.

&&

.SHORT TERM...
(Wednesday through Friday night)
Issued at 214 PM CDT Tue Apr 23 2024

The cold front (which should extend from central AR through
northwestern TN/southwestern KY and into southern OH at 12Z) will
advance southeastward over the course of the morning tomorrow,
warranting a low probability for light showers through mid-day.
Although there is still some uncertainty regarding how far south
the boundary will make it before stalling (especially given the
weak nature of the front), there is some agreement among the
various high-resolution and global models the it will shift
southward and out of the region during the afternoon hours.
Postfrontal clouds will likely scatter during the afternoon, with
highs once again reaching the l-m 70s.

Well to the west of our region, thunderstorms are expected to
develop across western OK early Wednesday morning as surface
pressure falls occurring across eastern portions of NM/CO force
the southwestern portion of the boundary to retreat northward as a
warm front. With this activity occurring beneath a broad axis of
30-40 knot NW flow aloft, there may be a tendency for upscale
growth into storm clusters that would subsequently spread
southeastward in the vicinity of the stalled frontal boundary
Wednesday night. However, with the front now expected to at least
temporarily clear our region, we will maintain a dry forecast
Wednesday night and increase POPs from SW-to-NE on Thursday as the
boundary begins to lift northeastward into our CWFA. Dewpoints in
the u50s-l60s across the moistening warm sector will promote
afternoon CAPE values in the 500-1000 J/kg range and this coupled
with 30-40 knot NW flow aloft may yield a few stronger storms
(especially across the western half of the CWFA).

The warm front is predicted to advance steadily northeastward
through the local area on Thursday night as a deepening lee
cyclone lifts northeastward over the central High Plains, and the
precipitation regime discussed previously will expand across most
of the region before ending across the northeastern portion of the
CWFA late Friday morning. In the wake of the warm front,
gradient-induced SSE flow will strengthen to around 15 MPH (with
gusts around 25 MPH) on Friday and Friday night. However, a
developing subsidence inversion aloft related to an amplified mid-
level ridge will keep conditions dry in spite of a increasingly
warm/moist airmass featuring highs in the u70s-l80s and lows in
the l-m 60s.

&&

.LONG TERM...
(Saturday through Tuesday)
Issued at 214 PM CDT Tue Apr 23 2024

A broad based trough will extend across the Central plains to the
Illinois/Ohio Valley are in the beginning of the period, bringing
the more-favorable upper level support for precipitation just
north and west of the entire TN Valley. For areas east and south
of this troughing, expect conditions to stay warm and dry as high
pressure will dominate the entire east coast of the US extending
into the Central Gulf Coast states. Conditions will also stay
warm/dry until the Sun-Mon timeframe as the trough begins to
translate further eastward. Dewpoints will remain in the U50s to
L60s until the frontal passage early next week (late Monday
night), but the best dynamics and synoptic support are expected to
remain north and west of the TN Valley until Monday. Some higher
wind gusts seem plausible as shortwaves translate across the upper
midwest, strengthening the pressure gradient and allowing a
stronger mass response for areas southwards.

&&

.AVIATION...
(00Z TAFS)
Issued at 632 PM CDT Tue Apr 23 2024

VFR weather should continue over the area for the TAF. A cold
front extending from the Great Lakes to West Texas will continue
moving to the SE, reaching this region a few hours after daybreak
Wed. Showers accompanying this boundary should fade as the front
nears the Tennessee Valley. Thus have stayed with a dry forecast
in the TAF. CIGs should lower into the 4-5kft range AGL as the
front nears. Chances for CIGs to MVFR (<3kft AGL) and/or a light
shower cannot be ruled out, but odds for this are too low for
inclusion in the TAF. SW winds tonight into early Wed should veer
to a NW direction as the front passes. CIGs should gradually
increase as we go into the afternoon hours Wed.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...None.
TN...None.
&&

$$

NEAR TERM...KTW
SHORT TERM....70
LONG TERM....IJ
AVIATION...RSB