459
FXUS64 KHUN 081714
AFDHUN

Area Forecast Discussion
National Weather Service Huntsville AL
1114 AM CST Wed Jan 8 2025

...New AVIATION...

.NEAR TERM...
(Rest of Today)
Issued at 950 AM CST Wed Jan 8 2025

Temps have been slow to rebound very much this Wed morning given a
persistent cloud deck coupled with continued weak CAA out of the
NNW. Current sat data though is showing some clearing moving into
west TN, as a reinforcing cold front approaches the MS River.
Provided some clearing develops going more into the afternoon hrs,
highs may be able to reach the mid/upper 30s for most spots. Even
with the slight warming trend, temps will still be around 15F
below normal for this time of the yr. Continue to bundle up later
today, especially as cooler air arrives by this evening.

&&

.SHORT TERM...
(Tonight through Saturday)
Issued at 222 AM CST Wed Jan 8 2025

The coldest night of the entire forecast package is expected
tonight as a weak boundary dips south across the the Tennessee
Valley. While no precip is expected, drier air should help push
the low level clouds out resulting in a mostly clear night.
Northerly CAA continues overnight pushing temperatures down into
the teens by daybreak. Combined with winds 5 to 10 mph, minimum
winds chills dip into the lower teens. Similar chilly conditions
are forecast for Thursday as afternoon highs peak in the upper 30s
to around 40F. Weather conditions take a drastic turn after
Thursday so make sure any last minute winter weather preparations
are completed by Thursday evening while conditions are ideal.

Our attention then turns to a potential significant winter storm
expected to impact the Tennessee Valley starting late Thursday
night through Saturday morning. An upper level trough begins to
dig down across the Rockies on Thursday and then merges with an
upper level low along the US/Mexico border. This wave then ejects
ENE towards the Gulf of Mexico where a surface low is expected to
form late Thursday. The low then pushes north and east across
MS/AL/GA during the day Friday. Snow begins to overspread the
area starting after midnight Thursday. Confidence continues to
increase regarding significant impacts starting at the onset of
snow and likely continuing through the weekend. Given cold
antecedent ground conditions, initial snowfall is expected to
stick to the ground and roadways making for hazardous travel
conditions.

There have been some changes in the forecast with the latest
round of model guidance. In particular, snowfall amounts continue
to trend upward. This was due in part to a combination of higher
QPF and colder temperatures. It appears as if the center of the
LLJ on Friday is forecast to be positioned a bit further to our
south across central AL, resulting in lower amounts of WAA and
reducing the wintry mix/fzra/sleet that initially cut into the
higher snowfall amounts. Any wintry mix that occurs is now
anticipated to primarily be south of the TN River with all snow
further north.

The most likely scenario (50th percentile) has 4-7 inches of snow
areawide with some locally higher amounts to 8 inches in the
higher terrain across northeast AL. The high end scenario (90th
percentile) shows 7-10 inches with higher amounts up to 12". As a
result, a Winter Storm Watch has been issued starting 06z Friday
and continuing through 12z Saturday morning. Even if snowfall
amounts fall short of expectations, area roadways will likely be
covered in snow and or ice making for treacherous travel.

Snow ends from west to east Saturday morning as the low pressure
system pushes north and east towards the Mid-Atlantic. While the
current forecast calls for temperatures to rise above freezing by
Saturday afternoon, it could be overdone especially if there is a
fresh snowpack on the ground. This scenario would limit the amount
of melting on Saturday. With snow on the ground and ideal
radiational cooling, temperatures Saturday night drop down into
the mid teens.

&&

.LONG TERM...
(Sunday through Tuesday)
Issued at 222 AM CST Wed Jan 8 2025

Below climatological normal temperatures continue through the
duration of the long term forecast period. A more zonal to slight
ridging upper level pattern begins to take shape starting Sunday.
Afternoon highs Sunday and Monday rise into the lower 40s, which
should assist with melting any residual snow on the roads. As we
head towards the middle of next week, another blast of cold air
begins to push in behind a quick moving shortwave Monday evening.
This will result in highs on Tuesday struggling to climb into the
upper 30s with overnight lows in the upper teens to lower 20s.

&&

.AVIATION...
(18Z TAFS)
Issued at 1114 AM CST Wed Jan 8 2025

Lingering MVFR cigs will continue for another couple of hrs before
cloud cover diminishes/sct from west to east. VFR conds are then
expected thru the remainder of the TAF period, as high pressure
quickly moves eastward across the region. NW winds near 8-9kt will
also become light/var this evening.

&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...Winter Storm Watch from late Thursday night through late Friday
     night for ALZ001>010-016.

TN...Winter Storm Watch from late Thursday night through late Friday
     night for TNZ076-096-097.

&&

$$

NEAR TERM...09
SHORT TERM....GH
LONG TERM....GH
AVIATION...09