840
FXUS64 KBMX 211757
AFDBMX

Area Forecast Discussion
National Weather Service Birmingham AL
1257 PM CDT Fri Aug 21 2026

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Issued at 1251 PM CDT FRI AUG 21 2026

- Heat: Major HeatRisk will continue today, with heat indices
  forecast between 105 to 109 degrees. Heat Advisory remains in
  effect.

- Thunderstorms: Severe storms are expected this afternoon across
  southern Central Alabama, with damaging winds and heavy rain
  remaining the main concerns.

&&

.DISCUSSION...
(This afternoon through Thursday)
Issued at 1251 PM CDT FRI AUG 21 2026

The KBMX radar reveals a few lingering showers from this
morning`s convective activity. A quick look at water vapor
imagery reveals an upper trough situated across the Tennessee
Valley and an upper ridge building out to our west. At the
surface, a cold front can be analyzed drifting slowly across the
northern half of the state. This boundary will continue its
southward movement through the day. Meanwhile, a shortwave will
round the base of the trough, triggering another round of
convection, generally to the south of the front. SPC maintains a
Marginal Risk (Level 1 out of 5) for the southern half of the CWA
due to the threat of damaging wind gusts. Forecast soundings once
again suggest ample instability, dry mid-level air, and high
DCAPE which supports the threat of downbursts with today`s
storms. Additionally, PWATs nearing 2" (per the 12Z KBMX sounding
and GOES TPW imagery) would lead to heavy rainfall and a
localized flash flooding threat.

Narrowing dew points, condensation pressure deficits falling to 2-
5mb and light winds in the wake of today`s convection will help
promote patchy fog development around sunrise Saturday morning.
Fog will be most likely for those that receive rain this
afternoon and evening.

Upper-level ridging will attempt to build in over the weekend.
Increased subsidence and drier air will lower rain chances
through the weekend, though precipitation looks to return early
next week as a series of shortwaves rotates through with the
northwest flow aloft.

High temperatures will continue in the low to mid-90s over the
coming days. Persistent humidity will promote daily heat indices
in the 105-109 degree range today. The Heat Advisory remains in
effect through 02Z Saturday. Drier air arriving this weekend will
help keep heat indices in check, generally in the 95-100 range.

95/Castillo

&&

.AVIATION...
(18Z TAFS)
Issued at 1251 PM CDT FRI AUG 21 2026

VFR conditions are currently in place across all terminals.
Similar to the last few days, scattered showers and storms are
likely this afternoon and evening. Convection will be more
isolated for BHM/EET/TCL and scattered for AUO/MGM. MVFR cigs/vis
and gusty winds will be likely with any passing storms. Will
continue with PROB30 mentions to account for this activity. As
winds become light overnight, there will be a low (20-30%) chance
for patchy MVFR fog around sunrise. Best chances will be at
terminals that receive rain this afternoon and evening.

Note: AMD NOT SKED for AUO due to a weather observation outage.

95/Castillo

&&

.FIRE WEATHER...

Relative humidity will generally remain elevated today, with
lingering moisture across the area. Low to moderate rain chances
will persist through today before a drying trend takes hold this
weekend. Drier air filtering into the area on Saturday will
result in a decrease in relative humidity (35 to 45%) for most
locations. However, wind speeds are expected to remain light,
which should negate any significant fire weather concerns during
this period. Moisture gradually begins to return early next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
Gadsden     70  94  70  92 /  10   0  10  10
Anniston    70  92  69  91 /  10   0  10  10
Birmingham  72  93  72  92 /  10   0  10  10
Tuscaloosa  73  98  73  96 /  10   0  10  10
Calera      72  94  72  93 /  20   0  10  10
Auburn      72  91  72  90 /  40   0   0   0
Montgomery  73  96  73  96 /  30   0   0   0
Troy        72  95  71  95 /  40  10   0   0

&&

.BMX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 9 PM CDT this evening for the following
counties: Autauga-Barbour-Bibb-Bullock-Chilton-Dallas-Elmore-
Fayette-Greene-Hale-Jefferson-Lamar-Lowndes-Macon-Marengo-Marion-
Montgomery-Perry-Pickens-Pike-Russell-Shelby-St. Clair-Sumter-
Tuscaloosa-Walker.

&&

$$

DISCUSSION...95/Castillo
AVIATION...95/Castillo