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FXUS64 KBMX 012321
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
521 PM CST Mon Dec 1 2025

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Updated at 520 PM CST MON DEC 1 2025

 - Significant rain amounts of one to two inches on average are
   expected across the southeast half of central Alabama through
   Tuesday. Highest rainfall amounts are expected along the I-85
   corridor.

 - Widespread freezing temperatures in the low to mid 20s will
   return Tuesday night through Wednesday morning. A few upper
   teens will likely be observed within the coldest valleys.

 - Another storm system is poised to arrive by the end of the
   upcoming week with an additional opportunity for soaking rains
   Thursday night through Friday night.

&&

.DISCUSSION...
(This evening)
Issued at 520 PM CST MON DEC 1 2025

Overall forecast is on track with temperatures and PoPs, so
changes will be minimal for the night. May wind up needing to
raise temperatures another degree or two in the north, but will
focus on the trends of the hourlies through the night. Bottom
line, the precipitation should move out before we even flirt with
32 degrees in the north/northwest.

16

Previous discussion:
(This evening through next Sunday)
Issued at 1250 PM CST MON DEC 1 2025

Today through Tuesday night:

A northern stream mid and upper-level trough will move eastward
across the Central CONUS tonight, while a weaker southern stream
disturbance moves along the Gulf Coast. The latter disturbance
will interact with a stalled frontal boundary over the northern
Gulf, causing weak cyclogenesis and a surface low lifting
northeastward across the Florida Panhandle and South Georgia.
While it`s taken a bit longer to saturate the column this
afternoon, strong isentropic lift will eventually result in
widespread light to moderate stratiform rain overspreading the
area by this evening. There initially will be two areas of rain,
one across the northwest counties with the northern stream system,
and another across the southeast counties with the southern stream
system, with the area in between eventually filling in. Heaviest
rainfall amounts will be across the southeast counties near the
deformation zone on the northwest side of the surface low and
where the PWATs will be highest. The right entrance region of an
upper-level jet streak will also be present. Not expecting any
flooding concerns outside of very poor drainage areas, just very
beneficial rainfall. Temperatures will be steady/rising slightly
overnight, not following a typical diurnal curve, then begin to
drop across the northwest as the cold front moves in.

Dry air aloft will cause precip to taper off into light
rain/drizzle tomorrow morning. Did slow down the exit of PoPs, but
moisture aloft will be exiting before the colder air arrives. Low
stratus/stratocumulus should linger for much of the day and
probably longer than models indicate, as is typical this time of
year. With strong northwest winds/cold air advection, it will be a
raw day with temperatures falling some in the afternoon, again
not following a typical diurnal curve. Winds become light
overnight, setting up good radiational cooling unless the low
clouds linger. Lows will drop well into the 20s, colder than it
has been in the last couple weeks.

Wednesday through Sunday:

Wednesday looks like the only day we will see a lot of sunshine
this week, though there may still be some cirrus clouds. Another
positively tilted trough will set up from the Great Lakes to the
Desert Southwest, with another southern stream disturbance along
the Gulf Coast. This will set up another isentropic lift
stratiform rain setup by Thursday, though there is some
uncertainty regarding how far north the rain will extend. Warm air
advection early Thursday morning is expected to be strong enough
to result in only liquid precipitation at onset. The shortwave
over the southwest CONUS will eventually move eastward while a
wave of low pressure forms in the Gulf, resulting in either
stratiform rain resuming or expanding in coverage depending on
whether a break in the rain occurs. Once again beneficial rain is
expected with the highest rain chances and amounts in the
southeast half of Central Alabama. Another shortwave this time in
northwest flow aloft may move through in the Sunday night/Sunday
timeframe, but rain chances remain low (10-20%). Temperatures will
remain below normal.

32/JDavis

&&

.AVIATION...
(00Z TAFS)
Issued at 520 PM CST MON DEC 1 2025

Widespread steady light to moderate rain will overspread the
area, along with IFR to LIFR cigs after 2 to 4z. Until then, we
will remain in two bands, one in the south with higher clouds and
the other in the northwest with MVFR clouds. Rain ends from west
to east tomorrow morning, but expect IFR cigs to linger through at
least midday, with MVFR through the rest of the period. Behind a
cold front, winds tomorrow will become northwesterly at 10 to 12
kts, with gusts up to 20 kts at times in the afternoon.

16

&&

.FIRE WEATHER...

Another round of soaking rainfall is expected to move across
Central Alabama this afternoon through early Tuesday morning. 1 to
2 inches of rainfall on average is anticipated across the
southeast half of Central Alabama. Dry weather returns by midday
Tuesday through Wednesday with MinRHs ranging from the mid 30s to
lower 40s once again by Wednesday afternoon. Additional rain
chances return for Thursday and Friday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     42  45  21  52 / 100  30   0   0
Anniston    45  47  24  53 / 100  40   0   0
Birmingham  41  44  25  52 / 100  30   0   0
Tuscaloosa  41  43  25  54 / 100  20   0   0
Calera      43  46  25  55 / 100  30   0   0
Auburn      50  53  29  53 / 100  50   0   0
Montgomery  50  54  28  54 / 100  40   0   0
Troy        53  55  29  55 / 100  40   0   0

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

DISCUSSION...16
AVIATION...16