528
FXUS64 KBMX 191437
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
837 AM CST Sun Jan 19 2025

...New SHORT TERM...

.SHORT TERM...
(This morning through midday)
Issued at 837 AM CST SUN JAN 19 2025

Ongoing forecast remains on-track, only made a few grid
adjustments for PoP/Wx through early afternoon. Low stratus will
persist over the entire forecast area through early afternoon as
the 19/12z BMX sounding sampled the frontal inversion top around
890 mb with a nearly saturated profile from this level toward the
surface while a slug of dry air was sampled generally above 820 mb
where a subsidence inversion was present. Moisture will remain
trapped within the lower roughly 110 mb through midday, followed
by a gradual mix-out from mid to late afternoon due to drier air
advecting in from the northwest along with maximized boundary
layer mixing. Until that time, low stratus with sufficient
moisture for some light showers or snow flurries is expected with
best potential generally across the northeastern third of the
area. While temperatures will decrease to below freezing far north
and northwest, intensities are expected to remain too light for
any accumulation and no impacts are anticipated.

05

Previous short-term discussion:
(Today through Monday)
Issued at 332 AM CST SUN JAN 19 2025

Key Messages:

-  Extreme Cold Warnings and Cold Weather Advisories in effect
   for Monday morning
-  Cold Weather Advisory likely to be extended through the week

The cold front is currently progressing through our southeastern
counties early this morning. In the wake of the front, temps have
dropped into the 40s. By sunrise, we will be down into the mid 20s
for our northwestern areas to the 40s across the southeast. We won`t
warm up too much today with highs topping out in the mid 30s to mid
40s for most. We continue with a low chance for light snow/flurries
across our northern counties through late this afternoon as wrap
around moisture meets these much cooler temperatures. Not expecting
much, if any, accumulations today. Otherwise for today, winds will
pick up out of the north with an occasional gust from 25-30 MPH. Not
confident enough in the duration and extent to issue a Wind Advisory
at this time.

The main story in the short term will be the arrival of dangerously
cold temperatures tonight into Monday morning. Low temperatures
tonight will plummet into the 10-20 degrees range. A brisk northerly
wind will result in wind chill values from 0-5 degrees across our
northern counties and 5-10 degrees across our southern tier. The
Cold Weather Advisory remains in effect for much of the CWA.
However, the northeastern counties and Jefferson county have been
upgraded to an Extreme Cold Warning. It`s likely that only the
northern half of Jefferson county will reach criteria but it would
only take us dropping another couple degrees for more of the county
to experience extreme cold conditions. There won`t be much relief on
Monday as many will struggle to warm above freezing. Those further
south will likely see the mid 30s. Another very cold night is
expected Monday night with lows dropping back into the mid teens to
around 20 degrees. Wind chill values from the 8 to 15 degrees range
will warrant another Cold Weather Advisory as we head into Tuesday.

95/Castillo

&&

.LONG TERM...
(Tuesday through next Saturday)
Issued at 332 AM CST SUN JAN 19 2025

Key Messages:

-  Winter weather is expected portions of Central Alabama Tuesday
   and Tuesday night, with impacts to travel extending into
   Wednesday morning. A Winter Storm Watch has been issued for
   areas generally south of I-20.

A positively-tilted shortwave trough is progged to rotate through
the broad longwave flow aloft on Tuesday, swinging through the
Southern Plains and the Appalachians. Forcing for ascent will
overspread the Gulf Coast region as a result, with isentropic
ascent extending into Central Alabama. This will allow for
moisture transport over a very cold airmass already in the region,
and areas of light snow are forecast to spread from west to east
Tuesday morning into the afternoon. This activity will battle dry
boundary layer conditions per various forecast soundings. Thus,
it appears our northern forecast area may only see flurries, or no
snow at all due to the drier low-levels. However, more moderate
snowfall is possible as an axis of 700 mb frontogenesis develops
across our southern counties. Depending on where this axis sets up
and how saturated the DGZ becomes, a brief period of heavier snow
could result late Tuesday afternoon into Tuesday evening.

All things considered, probabilities for measurable snow have
steadily increased over the past couple of nights per the NBM, and
a good portion forecast area could see winter weather impacts
Tuesday and Tuesday night. Roads could become slick due to snow
accumulations, especially as temperatures quickly fall in the
evening and overnight hours and our ground will already be cold.
Any partially melted snow could refreeze as ice during the
evening. Hazardous travel should be anticipated Tuesday into
Wednesday morning, particulary for areas along US Hwy 80 and I-85
where highest snow probabilities/accumulations exist. It`s worth
noting that due to the cold scenario, even light snow
accumulations could cause big travel problems. A Winter Storm
Watch has been issued for areas generally south of I-20 at this
time, though additional counties northward would see a Winter
Weather Advisory in future updates. A Cold Weather Advisory will
also be needed into Wednesday morning.

After the winter weather system departs Wednesday morning, a
subsequent period of cold, dry weather is forecast across the area
as another upper-level trough/disturbance swings through the eastern
CONUS. However, there`s hope on the horizon as heights begin to
recover toward the weekend with a modifying airmass. Temperatures
will begin to warm with southerly flow across Alabama, and there`s
some low rain chances northwest as a front approaches the
Tennessee Valley Saturday night.

40/Sizemore

&&

.AVIATION...
(12Z TAFS)
Issued at 525 AM CST SUN JAN 19 2025

MVFR/IFR ceilings are currently in place across the region.
Northwesterly winds have increased over the last few hours in the
wake of a front. Gusts to around 20-25 knots will be likely
through this evening, potentially through the night as well.
Ceilings will gradually lift to all MVFR by mid morning and to VFR
by this afternoon.

95/Castillo

&&

.FIRE WEATHER...

A cold front will move through the area today bringing Arctic air
into Central Alabama. Northwesterly 20 ft winds at 10-15 mph are
forecast with higher gusts. Winds become northerly on Monday at
5-10 mph with RH values 20-30% during the afternoon. Snow is
forecast for portions of Central Alabama on Tuesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     37  12  30  15 /  20   0   0   0
Anniston    39  15  31  17 /  20   0   0   0
Birmingham  37  15  30  18 /  10   0   0   0
Tuscaloosa  38  17  34  18 /   0   0   0   0
Calera      38  17  32  19 /  10   0   0   0
Auburn      44  20  34  21 /  10   0   0   0
Montgomery  44  20  36  21 /   0   0   0   0
Troy        47  19  37  20 /   0   0   0   0

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
Cold Weather Advisory from midnight tonight to 11 AM CST Monday
for the following counties: Autauga-Barbour-Bibb-Bullock-
Chambers-Chilton-Clay-Coosa-Dallas-Elmore-Fayette-Greene-Hale-
Lamar-Lee-Lowndes-Macon-Marengo-Marion-Montgomery-Perry-Pickens-
Pike-Randolph-Russell-Shelby-Sumter-Talladega-Tallapoosa-
Tuscaloosa-Walker-Winston.

Extreme Cold Warning from midnight tonight to 11 AM CST Monday
for the following counties: Blount-Calhoun-Cherokee-Cleburne-
Etowah-Jefferson-St. Clair.

Winter Storm Watch from Tuesday morning through late Tuesday
night for the following counties: Autauga-Barbour-Bibb-Bullock-
Chambers-Chilton-Coosa-Dallas-Elmore-Greene-Hale-Lee-Lowndes-
Macon-Marengo-Montgomery-Perry-Pike-Randolph-Russell-Sumter-
Tallapoosa.

&&

$$

SHORT TERM...05
LONG TERM....40
AVIATION...95