Marine Weather and Tide Forecast for Upper Grand Lagoon, FL

UPDATE
Issued at 1044 AM EDT Mon Aug 3 2026

The main update has been to trim roughly the western half of the Flood Watch, or roughly from Jefferson County westward. Water vapor imagery and satellite-derived PW imagery show drier mid- level air currently arriving west of the Flint and Apalachicola Rivers, which will limit further potential for excessive rainfall.
That drier air will continue to spread east this afternoon.

The Flood Watch continues over the eastern FL Big Bend. The air mass remains richly moist, and there are still a few few more hours left for the westerly cyclonic flow aloft to organize thunderstorms in training bands pointed inland from the Gulf.
Later this afternoon, we may be able to kill off the rest of the Flood Watch early... before its natural expiration this evening.

SHORT TERM
(Today and Tonight)
Issued at 319 AM EDT Mon Aug 3 2026

This discussion has probably been sounding like a broken record for the past couple of days. Another day of showers and thunderstorms with heavy rainfall amounts is expected. The upper level trough pulling in moisture from the southwest will keep the region primed for heavy rainfall through tonight.

The Flood Watch continues through this evening with an additional 1-3 inches and locally higher amounts of 4-6 inches possible.
During the afternoon and evening hours, most activity will be occuring over the FL Big Bend and along the I-75 corridor. We will start drying out in SE AL and SW GA counties as the shortwave lifts north today, allowing for drier air to filter in and lowering the rain chances. These counties may see 0.25-1" of rainfall, mainly this morning. PoPs decrease to 30% and less for the afternoon for areas along and west of the Flint/Apalachicola rivers. The WPC has the areas along and east of the Albany to Panama City line in a Marginal (level 1 of 4) risk for excessive rainfall with the extreme SE Big Bend in a Slight (2 of 4) risk today.

Temperatures for today will be in the upper 80s to around 90 degrees with light westerly/southwesterly winds. Lows will be in the low 70s.

LONG TERM
(Tuesday through Sunday)
Issued at 319 AM EDT Mon Aug 3 2026

The heavy rain threat has mostly passed. There will be showers and thunderstorms for Tuesday as the shortwave trough lingers north of the region, but weakening. PoPs for Tuesday are around 40-60 percent for the afternoon.

By midweek, we return to a more typical summertime pattern with PoPs around 30-40 percent for afternoon showers/thunderstorms.
Southwesterly flow continues for the long term, but PWATs are lower ranging around 1.5-2", lowering our chances for heavy rain rates. Temperatures return to seasonal averages with highs in the low 90s with heat indices ranging from 100-108 degrees, and isolated areas up to 112. Overnight lows will be in the low 70s.

AVIATION
(12Z TAFS)
Issued at 621 AM EDT Mon Aug 3 2026

A moisture gradient exists between drier low level air in SE AL and the FL panhandle and more moist air further east. Convection has been ongoing overnight through the Gulf waters into the FL Big Bend and southern GA. The drier air will gradually shift east today along with most of the convection. There is a possibility of SHRA redeveloping later today as a disturbance moves closer to the area along with daytime heating. For TAFs, have convection ending from west to east this morning from ABY-TLH then eventually at VLD. Low probs on where any SHRA redevelops later today and have kept out of TAFs. Some IFR reported this morning and at ABY with models showing improvement towards 13-14Z to VFR.

MARINE
Issued at 319 AM EDT Mon Aug 3 2026

Southwest winds of Cautionary levels will hold over Apalachee Bay today through this evening with 4-5 ft seas. Tonight, winds and seas will begin decreasing where we can see 2 ft waves and light to gentle southwesterly breezes through Tuesday. Winds are forecast to veer southerly by midweek and shift easterly towards the end of the work week. Scattered showers and thunderstorms will be possible each day.

FIRE WEATHER
Issued at 319 AM EDT Mon Aug 3 2026

Widespread wetting rains are expected to continue today, especially in the FL Big Bend and southern Georgia. This afternoon, districts west of the Flint and Apalachicola rivers will see a western shift in transport winds as drier air begins to filter into the region. Dispersions will increase over the FL and AL wiregrass regions to a moderate level. Fair to moderate dispersions can be expected area wide Tuesday through the rest of the week. However, afternoon showers and thunderstorms remain in the forecast as we return to a more typical summertime pattern with scattered PoPs of 30-60 percent.

HYDROLOGY
Issued at 1044 AM EDT Mon Aug 3 2026

A Flood Watch remains in effect for Dixie, Taylor, Lafayette, Madison and coastal Jefferson Counties. Guidance still shows potential for thunderstorms to re-form into a training band or two through this afternoon, which would then bring pockets of 3+ inch additional rain totals. If this occurs where heavier rain already occurred this past weekend, then flash flooding would be possible.
Once the threat of heavy rain has ended, we could cancel the remainder of the Flood Watch early.

Gaged rivers are running entirely below respective flood stages and well within their banks. Bear Creek (Bay County) has fallen below flood stage. Elsewhere, current trends in both rainfall and hydrographs suggest no additional river flooding is expected.

After today, we will transition back to a normal amount and rhythm of summertime convection. This means that flooding will revert back to the short-lived nuisance variety beneath core of heavier storms.

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 88 72 91 73 / 70 10 70 10 Panama City 89 76 90 77 / 20 20 20 10 Dothan 90 72 91 72 / 20 10 20 10 Albany 90 72 91 72 / 20 10 40 10 Valdosta 88 71 92 72 / 70 20 50 10 Cross City 86 73 91 73 / 90 50 30 20 Apalachicola 87 77 88 77 / 70 20 30 10

TAE WATCHES/WARNINGS/ADVISORIES
FL...Flood Watch until 8 PM EDT this evening for FLZ019-028-029-034- 118-128-134.

High Rip Current Risk through late tonight for FLZ108-112-114- 115.

GA...None.
AL...None.
GM...None.