768
FXUS64 KBMX 260056
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
756 PM CDT Wed Sep 25 2024

...New SHORT TERM...

.SHORT TERM...
(Tonight through Friday)
Issued at 756 PM CDT WED SEP 25 2024

Showers and storms associated with a pre-frontal trough have
largely pushed eastward into Georgia. Meanwhile the cold front
continues to move slowly southeastward through the area, with an
isolated shower at times along it and other boundaries. An upper
low remains centered near Paducah Kentucky, while Hurricane Helene
is strengthening over the southern Gulf. Overall rainfall rates
should be lower overnight, though even light to moderate rain
could cause minor flooding issues over portions of our southeast
counties where 2 to 5 inches of rain fell. Cooler air will also
work down into some of our far northern counties. As another vort
max rounds the base of the upper low, and convergence strengthens
along a surface trough north of Helene and old frontal boundary,
rain will increase again from east to west late tonight and
tomorrow. Heavy rainfall rates returning tomorrow will result in
an increasing flash flood threat. Temperatures will remain limited
across the east by precipitation, but will warm up more across
the west.

32/JDavis

Previous short-term discussion:
(This evening through Thursday)
Issued at 1218 PM CDT WED SEP 25 2024

Tonight, there could be a break in rain as the boundary weakens
and the outer bands of Helene move approach the coast. Scattered
activity will be possible, mainly in the east through the early
morning hours. The outermost bands of helene will begin to impact
the area beginning early Thursday, with widespread rain moving
south to north, with coverage increasing through the day as Helene
moves north. PW values will be at absolute max for this time of
year, with more consistent coverage, and higher accumulation
values in the east, with amounts decreasing incrementally the
farther west of I65 the bands reach. A Flood Watch will remain in
effect through Friday morning to account for the rain
accumulations from the scattered activity today, and the
widespread heavy rain expected to increase from Helene.

Winds will begin increasing in response to Helene by early
Thursday afternoon. A Tropical Storm Warning will be in effect
through Friday morning to account for increasing winds and high
rainfall totals.

24

&&

.LONG TERM...
(Friday through next Tuesday)
Issued at 337 AM CDT WED SEP 25 2024

Helene is expected to weaken to a tropical depression by Friday
morning and then quickly becomes absorbed into the larger-scale cut-
off low by Friday evening. There will be some wrap-around rainfall
across the northern half of Central AL during the day on Friday
before dry air gets wrapped in, decreasing the footprint of rainfall
around the cut-off low Saturday through Sunday. This cut-off low
persists over the region through at least Monday before shifting to
our east Monday night into Tuesday. I won`t completely rule out some
lingering shower activity under the closed upper level low over the
weekend, but most guidance keeps the area rain-free, so my
confidence to mention any rain chances is too low right now, but
it`s something we`ll need to watch for in the next few days.

25/Owen

&&

.AVIATION...
(00Z TAFS)
Issued at 629 PM CDT WED SEP 25 2024

Showers and storms have moved east of the terminals and should
remain there much of the night, though some isolated to scattered
showers will remain possible (20-40% chances). MVFR cigs continue
to linger near MGM, while the other terminals should remain VFR
for much of the night. Deteriorating conditions are expected
Thursday as Hurricane Helene approaches the Gulf Coast. Rain will
move back westward, while thunder probabilities will be too low to
mention at this time. MVFR to IFR cigs and visibilities will be
expected except at TCL, while any gusts above 25 kts will hold
off until after the current TAF cycle.

32/JDavis

&&

.FIRE WEATHER...

With tropical moisture increasing ahead of Hurricane Helene and a
stalled frontal boundary, widespread rain is expected through
Thursday, with rain chances diminishing through the day on Friday.
Minimal RH values will be above 60% through the weekend. Winds
increase substantially on Thursday as the tropical system
approaches the northern Gulf coast. Wind gusts of 25-30 mph are
possible for much of Central Alabama, with gusts exceeding 40mph
in the eastern half of Central AL.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     63  75  62  74 /  40  90  90  70
Anniston    65  74  65  76 /  50 100 100  60
Birmingham  64  77  64  73 /  30  60  80  60
Tuscaloosa  65  81  63  75 /  20  30  60  50
Calera      66  77  65  75 /  30  60  80  50
Auburn      68  75  65  77 /  80 100 100  30
Montgomery  70  77  65  79 /  60  90  90  20
Troy        69  75  63  78 /  80 100 100  20

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
Flood Watch from Thursday afternoon through Friday morning for
the following counties: Autauga-Blount-Chilton-Jefferson-Lowndes-
Shelby.

Wind Advisory from 7 PM Thursday to 1 PM CDT Friday for the
following counties: Autauga-Blount-Calhoun-Chilton-Clay-Coosa-
Elmore-Etowah-Jefferson-Lowndes-Montgomery-Shelby-St. Clair-
Talladega-Tallapoosa.

Flood Watch through Friday morning for the following counties:
Barbour-Bullock-Calhoun-Chambers-Cherokee-Clay-Cleburne-Coosa-
Elmore-Etowah-Lee-Macon-Montgomery-Pike-Randolph-Russell-St.
Clair-Talladega-Tallapoosa.

Tropical Storm Warning for the following counties: Barbour-
Bullock-Chambers-Cherokee-Cleburne-Lee-Macon-Pike-Randolph-
Russell.

&&

$$

SHORT TERM...32/JDavis
LONG TERM....25
AVIATION...32