398
FXUS62 KTAE 201755
AFDTAE

Area Forecast Discussion
National Weather Service Tallahassee FL
Issued by National Weather Service Mobile AL
155 PM EDT Thu Aug 20 2026

...New AVIATION...

.KEY MESSAGES...
Issued at 155 PM EDT Thu Aug 20 2026

- Long-duration hazardous heat wave continues through the end of
  the week. Heat products will keep being issued accordingly.
  Please exercise heat safety: www.weather.gov/safety/heat.

- Daily chances for thunderstorms remain in the forecast. Strong-
  gusty winds, frequent lightning and locally heavy rain are the
  main threats. Highest rain chances are Friday-Saturday.

- The heat wave is poised to break late this week or early
  weekend, which likely opens the door for convectively active
  weather. A more typical summertime pattern returns early next
  week.

&&

.SHORT TERM...
(Today and Tonight)
Issued at 238 AM EDT Thu Aug 20 2026

Hazardous heat and robust thunderstorms will once again dominate
today`s forecast thanks to strong high pressure, nearby frontal
boundary to our north, and upper-level low over the FL Peninsula.
A Heat Advisory goes into effect along/south of the FL state line
for heat indices between 108 & 112 degrees - 11AM EDT/10AM CDT to
8PM EDT/7PM CDT. High temperatures in the 90s will be common with
lows in the 70s. An isolated location or two may reach 100 (e.g.,
Valdosta, Albany). The only meaningful relief will be from
thunderstorms.

In terms of convection, we are looking at an early start offshore,
followed by a gradual spreading inland over the FL Big Bend, then
further development from storm outflow boundary collisions along
the I-10 corridor. Additional cells/clusters are expected to
develop around the Wiregrass via frontal forcing. Strong
instability, a deep mixed layer, and satellite-derived
Precipitable Water around 2" support a threat of strong to severe
thunderstorms capable of strong to isolated damaging gusts,
frequent lightning, locally heavy rain, and some hail. The Storm
Prediction Center has a Marginal Risk (level 1 of 5) for much of
the Tri-State area in their Thursday Outlook.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 238 AM EDT Thu Aug 20 2026.NEAR TERM...

The long-duration heat wave is finally poised to break in response
to an amplifying Eastern US trough that sends a frontal boundary
farther southward into the region. A tradeoff is higher rain
chances, so expect a period of unsettled weather Friday-Saturday,
followed by improvement come Sunday. We will also have to be on
guard being positioned in NW aloft with the ridge retrograding to
the western US (i.e., Mesoscale Convective Systems).

All signs point to more of a seasonable late-summer feel for much
of next week such that widespread heat products are not
anticipated. High temperatures are forecast to be in the low to
mid 90s (heat indices several degrees higher). Overnight lows drop
to the low 70s away from the immediate coast. Thunderstorms
remain possible each day, but likely more run-of-the-mill variety
for the latter part of August.

&&

.AVIATION...
(18Z TAFS)
Issued at 155 PM EDT Thu Aug 20 2026

VFR conditions are generally expected to prevail through Friday
morning. PROB30 remains in place from 20/21z until 20/24z for
potential thunderstorms impacting area terminals this afternoon
where gusty winds and brief MVFR to IFR conditions are possible.

&&

.MARINE...
Issued at 238 AM EDT Thu Aug 20 2026

Elevated thunderstorm chances are forecast through this weekend
thanks to weakening high pressure in response to a frontal
boundary sagging into the Deep South. Maritime convection will
pose a threat for strong to gusty winds, frequent lightning, low
visibility from heavy rain, and potential waterspouts. Otherwise,
gentle to moderate west winds are prevail with daily afternoon
seabreezes across the immediate nearshore legs.

&&

.FIRE WEATHER...
Issued at 238 AM EDT Thu Aug 20 2026

The main fire concerns continue to be hazardous heat conditions
persisting for at least one more day and daily chances for
afternoon thunderstorms. The heat wave is poised to break heading
into the weekend.

High temperatures well into the 90s will be common with heat
indices up to 112 degrees, primarily along/south the FL state line
today. Thunderstorms will be capable of frequent lightning,
gusty/erratic winds (some strong to severe), and locally wetting
rains are additional threats.

Prevailing west to NW winds are forecast outside of daily
afternoon seabreezes across our FL counties, but become more
variable Friday- Saturday thanks to the presence of a frontal
boundary. The latter likely brings a period of unsettled weather
during that time.

&&

.HYDROLOGY...
Issued at 238 AM EDT Thu Aug 20 2026

Thunderstorms will be capable of producing localized nuisance
flooding in urban, poor-drainage, and low-lying areas. Some
isolated locations may see 2 to 3+ inches in a brief period of
time from the strongest storms, as observed yesterday in parts of
Bay County, FL. Such a scenario could foster small-scale flash
flooding. Otherwise, there are no significant hydrological
concerns the next several days. All area rivers are currently
running well below action stage.

&&

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when
they occur by calling the office or tweeting us @NWSTallahassee.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   98  75  95  74 /  20  10  60  50
Panama City   93  78  92  77 /  20  20  30  50
Dothan        97  74  95  73 /  20  20  50  50
Albany       100  75  97  73 /  20  10  60  60
Valdosta      99  74  96  73 /  10  10  60  40
Cross City    95  74  93  74 /  40  10  50  40
Apalachicola  92  77  90  77 /  40  20  40  50

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory until 8 PM EDT /7 PM CDT/ this evening for
     FLZ007>019-027>029-034-108-112-114-115-118-127-128-134-326-
     426.

     High Rip Current Risk through late tonight for FLZ114.

GA...Heat Advisory until 8 PM EDT this evening for GAZ155>161.

AL...Heat Advisory until 7 PM CDT this evening for ALZ065>069.

GM...None.
&&

$$

SHORT TERM...IG3
LONG TERM....IG3
AVIATION...WFO MOBILE
MARINE...IG3
FIRE WEATHER...IG3
HYDROLOGY...IG3