Area Forecast Discussion
Issued by NWS Birmingham, AL

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
717
FXUS64 KBMX 212323
AFDBMX

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

...New AVIATION...

.KEY MESSAGES...
Issued at 622 PM CDT FRI AUG 21 2026

- Heat: Minor HeatRisk will continue through the weekend. Heat
  indices are forecast to remain below 105 degrees.

- Thunderstorms: Severe storms are expected through early evening
  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...
(00Z TAFS)
Issued at 622 PM CDT FRI AUG 21 2026

A batch of rain is currently moving right over EET, between TCL
and BHM. Look for the activity to remain possible through 02Z for
the north. MGM and AUO may see some additional activity after 00Z
through 03Z. 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. Dry conditions are expected through much of the area on
Saturday.

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

16

&&

.FIRE WEATHER...

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...16