Area Forecast Discussion
Issued by NWS Huntsville, AL

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761
FXUS64 KHUN 311035
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
435 AM CST Fri Jan 31 2025

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

.NEAR TERM...
(Today)
Issued at 435 AM CST Fri Jan 31 2025

A mid-level cyclone currently resides across central MO, with a
broad belt of 80-90 knot SW flow aloft in place across the TN
Valley within the gradient between the low and subtropical high
centered across the Greater Antilles/southeastern Bahamas. In the
lower-levels, a gradually deepening area of low pressure will lift
northeastward across MO and into west-central IL by 12Z, with an
extensive band of light-moderate rain and embedded thunderstorms
progressing slowly eastward through our region in advance of a
surface trough axis that will eventually veer moderately strong
southerly flow to the south-southwest. Although dewpoints have
recovered into the m-u 50s, SPC mesoanalysis data suggests that
MUCAPE remains in the 100-200 J/kg range at most, and with a 55-65
knot SSW low-level jet predicted to veer and subside by sunrise,
we are not expecting any organization to the convective elements
within the broader band of precipitation.

Over the course of the day, the previously mentioned mid-level
cyclone will open into a positively-tilted trough and shift slowly
east-northeastward into the Upper OH Valley, as the related
surface low tracks eastward into central PA. This configuration
will result in a slower progression of the initial precipitation
band across our region, with it now predicted to spread slowly
eastward and out of the region between 18-21Z. However, solutions
from the 0Z HREF and global models all suggest that redevelopment
of showers and thunderstorms will occur by mid-afternoon across a
broad region from central KY southwestward into the Mid-South
region. This will occur as deep-layer ascent strengthens ahead of
the approaching shortwave trough, and as temps rise into the l-m
60s, steepening low-level lapse rates in the wake of morning
precipitation. Although CAPE may be a bit higher, ensemble data
still suggests 100-200 J/kg at most, with lightning the greatest
concern.

&&

.SHORT TERM...
(Tonight through Sunday night)
Issued at 435 AM CST Fri Jan 31 2025

Late afternoon showers and thunderstorms will likely continue
beyond 0Z this evening, but should spread east-southeastward with
time and exit the region by 3Z as the initiating mid-level trough
translates further eastward and away from the region. A cold front
will veer low-level flow to the NNW for most of the CWFA by
Midnight, with widespread postfrontal stratus clouds expected to
blanket the region during the early morning hours on Saturday.
With the incoming airmass Canadian in origin, temperatures will
likely fall into the lower 40s by sunrise (although this could be
a few degrees warmer due to the presence of low clouds).

Data from the most recent suite of global models suggests that an
unamplified westerly flow aloft will set up across the TN Valley
from Saturday-Sunday night, while light SE return flow gradually
develops from Saturday afternoon-Saturday evening as a high
pressure cell shifts southeastward across New England and a
northern stream trough (dropping southward along the Pacific Coast
of British Columbia) induces development of a surface low in the
lee of the northern Rockies. Although periods of enhanced cloud
cover may occur on Saturday/Saturday night, conditions will remain
dry and mild with highs returning to the l-m 60s Sunday (after
only reaching the m-u 50s Saturday) and lows remaining in the l-m
40s.

&&

.LONG TERM...
(Monday through Thursday)
Issued at 435 AM CST Fri Jan 31 2025

In the extended portion of the forecast, present indications are
that zonal flow aloft will persist across the local forecast area
for much of the new work week, as our region will remain located
along the northern rim of a strong subtropical ridge centered well
to our southeast. Light-moderate southerly low-level flow will
continue at the surface, to the south of a developing warm front
that will extend eastward into the OH Valley from a new area of
low pressure across the southern High Plains. This, coupled with a
west-southwesterly low-level jet of 20-25 knots, will result in
warm afternoon temps in the l-m 70s, with lows increasing as well
(into the u50s-l60s by Wednesday/Thursday mornings). As dewpoints
finally begin to increase into the u50s-l60s by Tuesday night, low
stratus clouds will become more common across the region, with a
few showers/thunderstorms possible as well. However, we have kept
POPs ~20% through Wednesday night and increased them to ~30-40% on
Thursday (at which time moisture may begin to pool across the
region ahead of a stronger cold front dropping southeastward
through the Mid-MS Valley).

&&

.AVIATION...
(06Z TAFS)
Issued at 1151 PM CST Thu Jan 30 2025

VFR conditions are expected at both terminals through 7-8Z. LLWS
is expected at the start of the TAF period at both terminals where
around 2000 feet winds will increase to around 45 knots from the
SSW. More persistent MVFR or lower CIG/VSBY restrictions are
expected as widespread rain and maybe a few -TSRA move into the
terminals after 07Z to 08Z with continuing LLWS around 45 knots
from the SSW. Around 15Z at KMSL (maybe a tad sooner), expect
precipitation to end, though MVFR CIGS will linger. -RA may
persist at bit longer at KHSV into the early afternoon hours
before ending with lingering MVFR CIGS continuing. A PROB30 group
was included for possible redevelopment in the late afternoon
hours of a few showers.

&&

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

&&

$$

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