930
FXUS64 KBMX 181111
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
611 AM CDT Mon Aug 18 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 603 AM CDT MON AUG 18 2025

 - Medium to high chances of heat indices reaching 105 degrees
   Monday through Wednesday for areas mainly along and west of
   I-65.

&&

.SHORT TERM...
(Tonight through Tuesday)
Issued at 1143 PM CDT SUN AUG 17 2025

Monday, high pressure will remain the main story, with northeasterly
flow prevailing between the high centered to the west and the low
moving slowly along the western Atlantic. CAMs are really trying
to bring in dry air with PW values less than the 75th percentile
for this time of year. This would have a large influence on the
amount of dry air throughout the atmospheric profile and storm
development. A few other models are holding on to moisture
remaining high, with PW values closer to the 75th and 90th
percentile. Will hedge a little higher than the CAMs for moisture,
as moisture has been overperforming the past week.

Through the afternoon, isolated development is expected with
instabilities meager with a couple thousand J/kg and lowered LI
values (even accounting for higher moisture). DCAPE will be
around 1100 J/kg, so any storms that can develop will have a
chance for strong downburst winds.

Highs will be in the mid to upper 90s, with higher values in the
west closer to the center of the high pressure. With the anticipated
moisture, heat indices will be in or close to the triple digits,
with a few areas in the west seeing up to 105 degree values. This
Advisory criteria may be more isolated, but with lows consistently
in the low to mid 70s, the heat will allow for little breaks and
recovery, thus more impacts.

Tuesday will be much of the same scenario as Monday, with all models
trying to show a decrease in moisture through the afternoon. How
much and if any will depend on how closer Erin makes it to the east
coast. Isolated diurnal convection is again possible, though chances
will be a lot lower for much of the area, with lowered instabilities
and LI values. Right now, leaning dry and have most of the area
rain free, except for the far east. Heat will again be a concern
with less cloud coverage, and heat indices could again be near or
at triple digits through the afternoon. Heat Advisories are in
place for areas west of I65 through Tuesday afternoon, covering
the nighttime hours to account for the higher low temperatures
that would add to the heat stress.

24

&&

.LONG TERM...
(Tuesday night through next Sunday)
Issued at 1143 PM CDT SUN AUG 17 2025

Wednesday will be a repeat of Tuesday, with a large influence from
how close Erin moves along the coast. Northeasterly flow will
increase moisture as the tropical cyclone creates an area of
increased rain over the SE CONUS. Activity here could linger
through the night. By Thursday, low level flow should shift to a
more southwesterly to westerly direction as the high pressure
continues to drift to the west, and a low pressure and trough
develops over the northern Plains and begins to move east.
Moisture will return with PW values returning to the 90th
percentile or max values. Scattered activity will be possible each
afternoon, increasing in coverage through the weekend as the
trough should swing a boundary through the area.

Temperatures on Wednesday will remain in the low to mid 90s, with
heat indices approaching triple digits. By Thursday, there should be
enough cloud cover and convection that temperatures will drop into
the upper 80s and low 90s. This would drop heat indices to below
triple digits in most places, which should continue through the
weekend.

24

&&

.AVIATION...
(12Z TAFS)
Issued at 603 AM CDT MON AUG 18 2025

VFR conditions are prevailing across all terminals with the
exception of ASN where patchy fog has developed. There is a small
window over the next hour or two for patchy fog at EET/TCL but
confidence is low so have left out of the TAF. Added in a mention
of PROB30 at MGM/AUO as the latest CAMS continue to hint at
convection across our southern areas this afternoon. Any activity
further north will be isolated. Winds remain light outside of any
convection through this cycle.

NOTE: AMD NOT SKED has been added at TCL until
further notice due to comms issues.

95/Castillo

&&

.FIRE WEATHER...

Minimum RH values will generally be in the 40 to 55 percent range
the next couple afternoons with showers and storms remaining
isolated to widely scattered. 20ft winds will remain light.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     95  73  93  72 /  20  10  20  10
Anniston    93  72  92  72 /  20  10  20  10
Birmingham  94  75  93  74 /  20  10  10  10
Tuscaloosa  95  75  96  74 /  20  10  10  10
Calera      94  74  93  72 /  20  10  10  10
Auburn      93  73  92  72 /  20  10  20  10
Montgomery  94  74  94  74 /  20   0  10  10
Troy        93  72  93  72 /  20   0  10  10

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT Tuesday for the following counties:
Fayette-Greene-Lamar-Marion-Pickens-Sumter-Tuscaloosa-Walker.

Heat Advisory from noon today to 8 PM CDT Tuesday for the
following counties: Bibb-Blount-Chilton-Dallas-Hale-Jefferson-
Marengo-Perry-Shelby-Winston.

&&

$$

SHORT TERM...24
LONG TERM....24
AVIATION...95/Castillo