977
FXUS64 KBMX 170152
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
852 PM CDT Mon Sep 16 2024

...New SHORT TERM, AVIATION...

.SHORT TERM...
(Tonight through Wednesday)
Issued at 834 PM CDT MON SEP 16 2024

Mid and upper level cloudiness covered much of the southwestern
two thirds of the area this evening. Showers will remain limited
to the far southwest and it will diminish completely by 10 pm.
Drier air will continue slowly filtering in from the northeast
overnight. These clouds and drier conditions will allow a low
temperature gradient from northeast to southwest overnight. Due to
the cooling and residual ground moisture, some localized fog may
develop around sunrise. Otherwise, no changes planned to the
messages overnight into Tuesday.

75

Previous short-term discussion:
(This afternoon through Tuesday)
Issued at 1253 PM CDT MON SEP 16 2024

Mostly rain-free conditions are ongoing across much of Central
Alabama today, thanks to some drier air advecting in from the
northeast both at the surface and at the mid-levels of the
atmosphere. Mostly sunny skies aside from some scattered cu is
being observed across eastern and northeastern counties, where
highs today should be able to reach into the mid 80s. Meanwhile,
the remnant low of what`s left of Francine continues to slowly
move westward across Louisiana. A narrow corridor of showers
continues to persist thanks to some lingering isentropic lift
across Sumter and Marengo Counties this afternoon, along with
broken mid-level clouds present across the southwestern half of
Central Alabama. As drier air continues to filter into the region,
clouds are expected to gradually decrease by this afternoon and
evening, with rain chances also coming to an end. Highs are
currently on track for the most part, but have been raised a few
degrees where clouds have dissipated a bit earlier than expected.
Highs should reach close to 80 degrees in the far southwest
counties with mid to upper 80s expected elsewhere.

Clouds are expected to mostly clear out overnight tonight, with
temperatures dropping down into 60s areawide. As the temperatures
drop toward the dewpoint with moist ground conditions and mostly
calm winds, patchy fog will likely form during the early morning
hours on Tuesday. There are still some uncertainties in terms of
how low visibilities may get, but guidance trends are indicating
that the boundary layer will likely decouple. We`ve added in at
least patchy fog to the forecast to trend in that direction, and
that may need to be updated as we go into the evening hours.

Going into the day on Tuesday, an overall weakness in the 500mb
pattern will emerge over much of the region, stretching from the
central Gulf Coast northeastward to the Mid-Atlantic states. The
potential tropical cyclone located just off the South Carolina
coast will move inland to the northwest and become cut off from
the main upper level flow. As the center of the low moves over the
heart of the Smoky Mountains, we`ll stay on the dry southwest side
of the system. The only mention of PoPs will be across the
extreme southern counties as as warm front tries to lift northward
from the Gulf Coast. The front should eventually stall across
southern Alabama as it encounters northerly to northwesterly
surface flow on the west side of the closed low over the Smokies.
Dewpoints should be fairly comfortable with the northerly flow
Tuesday afternoon in the 60s and even upper 50s across the far
northeast counties. High temperatures with plenty of sunshine
should top out in the mid to upper 80s areawide.

56/GDG

&&

.LONG TERM...
(Tuesday night through Sunday)
Issued at 327 PM CDT MON SEP 16 2024

A slow-moving closed low will be centered over North Carolina on
Wednesday with northwest flow across Alabama. As the low wobbles
westward PWAT values may modestly increase, potentially supporting a
non-zero chance of showers over eastern Alabama aided by daytime
heating. However, there is not enough confidence to include rain in
our newest forecast. As the trough begins to move eastward and a
ridge amplifies to our west, a drier airmass will move in from the
north. This pattern should continue through Sunday, resulting in an
extended period of dry weather.

87/Grantham

&&

.AVIATION...
(00Z TAFS)
Issued at 834 PM CDT MON SEP 16 2024

Mid and upper level cloudiness will continue over a large part of
the area overnight. But some clear to partly cloudy conditions
will develop as the drier air moves in from the northeast. Due to
some cooling overnight and the residual moist ground conditions,
some patchy fog may develop toward sunrise. Overall, VFR
conditions will dominate with light winds overnight. Winds become
northwest around 5kts on Tuesday.

75

&&

.FIRE WEATHER...

A low chance of rain will persist across the southern and
southwestern portions of our area through Tuesday. Drier
conditions with northwesterly flow is expected for the second
half of the week. 20 foot winds should remain less than 10 mph
through Thursday. Afternoon RH values above 40 percent are
expected through Thursday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     60  86  59  85 /  10   0   0  10
Anniston    62  86  62  85 /  10   0   0  10
Birmingham  64  86  62  86 /  10   0   0   0
Tuscaloosa  65  87  62  87 /  10   0   0   0
Calera      65  87  64  86 /  10   0   0   0
Auburn      64  85  65  86 /  10  10   0  10
Montgomery  66  87  66  89 /  20  10   0  10
Troy        65  85  65  87 /  20  20   0  10

&&

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

$$

SHORT TERM...75
LONG TERM....87/Grantham
AVIATION...75