713
FXUS64 KHUN 231746
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
1146 AM CST Sun Feb 23 2025

...New AVIATION...

.NEAR TERM...
(Rest of Today)
Issued at 1002 AM CST Sun Feb 23 2025

A low-amplitude ridge at the 500-mb level will spread across the
Gulf Coast states this morning, in advance of a mid-level trough
that will track eastward from north-central TX into the Lower MS
Valley (acquiring a neutral tilt with time). In response to the
motion of the trough, a deepening area of low pressure will lift
east-northeastward off the coast of LA, with latest model guidance
suggesting that the cyclone`s stratiform precipitation shield
will advance northeastward into northern MS/central AL by 0Z. Due
to some uncertainty regarding how far this regime will extend into
our CWFA, we have included a low (10-20%) POP for light rain
across our southwestern forecast zones prior to sunset. However,
given the lingering presence of a dry subcloud layer, there is a
high likelihood that radar echoes aloft will evaporate into virga,
with perhaps just some sprinkles of rain at ground level. Surface
winds will remain light/variable throughout the day, as our
region will be embedded within a weakening ridge of high pressure
that will slowly shift northeastward into the central
Appalachians. In the absence of thermal advection, afternoon temps
will be dependent on how quickly cloud layers aloft become
broken-overcast in coverage, and for this reason we have
advertised highs in the u40s-l50s.

&&

.SHORT TERM...
(Tonight through Tuesday night)
(Issued at 239 AM CST Sun Feb 23 2025

By this evening, some locations in Franklin, extreme southern
Lawrence, and Cullman counties in AL could see the boundary layer
saturate enough for a very low chance of very light rain making
it to the ground. Not much accumulation is expected, only a few
hundreths at best. This possibility should continue until just
after midnight and then push southeast of the area. Several models
have the area quickly clearing out after midnight. This could set
the stage for more widespread freezing fog late Sunday night into
early Monday morning.

The good news is that the temperatures really begin to rebound
again on Monday, as warm air advection and abundant sunshine
are in place ahead of a front to our northwest. Highs should top
out at least in the upper 50s to lower 60s. Monday night should
not be as cold with continued warm air/moisture advection in
place. Lows in the mid 30s to around 40 degrees are expected.
This may be a good night for fog development, but it should not be
of the freezing variety.

As the front gets closer to the area on Tuesday, the low level
winds ahead of the front and associated warm air advection as
well. With continued abundant sunshine, highs will continue to
climb into the mid to upper 60s. Lows will also be warmer Tuesday
night and only drop into the upper 30s to lower 40 despite clear
skies. Stronger winds should keep fog at bay Tuesday night.

&&

.LONG TERM...
(Wednesday through Saturday)
Issued at 239 AM CST Sun Feb 23 2025

Zonal flow aloft at the start of the long term will give way to a
shortwave trough on Thursday, followed by generally northwest flow
through Saturday. Surface high pressure stretching from Virginia, the
Appalachians, and down over the northern Gulf coast on Wednesday
will be pushed southeast as a cold front approaches the South. This
is a trailing cold front associated with a low pressure system slated
to traverse the Great Lakes from Wednesday through Thursday. Still
anticipating the cold front to sweep over the Tennessee Valley
Wednesday night into Thursday morning.

This pattern will bring increased chances of showers (low to medium,
20-40%) Wednesday evening/night. Low shower chances (10-30%) will
linger on Thursday as the system quickly departs to the southeast.
Confidence on any thunderstorms is low, as guidance indicates no
surface instability and very minimal elevated instability (and only
for a couple hours during the early evening hours). Additionally,
forecast rainfall has increased slightly, but still remains on the
low side (less than a quarter of an inch); therefore, confidence in
flooding from these showers is low as well. Once this system moves
out of the area, dry weather will return through the first part of
the weekend.

Forecast temperatures will fluctuate a bit through the period, with
highs starting out in the upper 60s to lower 70s on Wednesday.
Temperatures are then expected to cool into the mid to upper 50s on
Thursday due to cold FROPA. This will be followed by a slight warm up
into the lower to mid 60s by Saturday afternoon. Lows will follow a
similar trend, as temperatures merely dip into the 40s Wednesday
night and cool into the mid to upper 30s Thursday night. Temperatures
in the upper 30s to lower 40s will then round out the work week
Friday night.

&&

.AVIATION...
(18Z TAFS)
Issued at 1146 AM CST Sun Feb 23 2025

The coverage of high-level Cs will gradually increase at the
HSV/MSL terminals this aftn as a strengthening area of low
pressure tracks northeastward through the northwestern Gulf.
Although some very light rain (or virga) on the northeastern edge
of this system may impact locations south of the TN River late
this aftn and this evening, confidence in precip at the TAF sites
was not high enough to include in this forecast update.
Regardless, ceilings will descend into the 10-15 kft range thru
10-12Z, which is when clouds will begin to disperse with the
departure of the low pressure to the east. Sfc winds will remain
lgt/vrbl for much of the forecast period due to the influence of a
broad ridge of high pressure, and this may support brief
development of FZBR/FZFG as clouds dissipate close to sunrise.

&&

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

&&

$$

NEAR TERM...70/DD
SHORT TERM...KTW
LONG TERM...26
AVIATION...70/DD