525
FXUS62 KJAX 181201
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
801 AM EDT Mon Aug 18 2025

...New AVIATION...

.AVIATION...
(12Z TAFS)
Issued at 801 AM EDT Mon Aug 18 2025

Showers developing along the Atlantic coast early this morning
will tend to increase in coverage and intensity as activity
migrates slowly inland towards the Interstate 95 corridor before
15Z. Embedded thunderstorms are expected to develop within this
activity towards 15Z along the southeast GA coast, and we added
a TEMPO group for IFR visibilities to the SSI TAF through around
18Z, with TEMPO groups added this afternoon at the northeast FL
terminals for brief wind gusts around 30 knots and MVFR
visibilities during heavier downpours. Convection should shift
west of the SSI terminal by 20Z, with VFR conditions then
prevailing thereafter. Convection will shift to the west of the
Duval County terminals and SGJ before 23Z and west of the GNV
terminal by 01Z, with VFR conditions prevailing thereafter.
Periods of IFR visibilities are likely at VQQ during the predawn
hours on Tuesday. Light north-northwesterly surface winds early
this morning will shift to northeasterly by 15Z, with speeds
increasing to 5-10 knots before 16Z and will then shift to east-
northeasterly by 18Z, with speeds increasing to 10-15 knots by
19Z. Speeds will gradually diminish at the regional terminals
after 23Z.

&&

.NEAR TERM...
Issued at 135 AM EDT Mon Aug 18 2025

Patchy inland morning fog and low stratus were forming inland
under mostly clear skies, light winds and saturated grounds. A
surface front was draped across north Florida, and as high
pressure strengthens north of the region today, the front will
shift farther south. Breezy onshore ENE winds bringing early
morning coastal showers onshore and a more dominant east coast sea
breeze regime into the afternoon.

Showers and storms will develop along the inland progressing east
coast sea breeze midday and translate inland toward the west into
the afternoon. The most numerous showers and storms are expected
west of the Highway 301 corridor across NE FL through early
evening where low level boundaries merge under a weakening mid
level trough. Drier air (PWAT < 2 inches) across our northern SE
GA near the Altamaha River will bring lower rain chances today.

The main convective hazards in storms today will be localized
flooding rain mainly across NE FL where higher moisture, weaker
storm motion and upper level instability coincide over low level
boundary mergers this afternoon. Mid level temperatures around
-6.7 to -6.9 degC at 500 mb are also near to just below climo
for this time of year, which could promote a few stronger
downdrafts/wet downbursts across NE FL this afternoon and evening.

Temperatures will trend warmer today given more sunshine, with
highs in the lower 90s inland to upper 80s coast. Peak heat index
values range between 100-105 degF. Tonight, near climo lows in the
lower 70s are expected inland with onshore flow keeping the coast
warmer with lows in the upper 70s to near 80.

&&

.SHORT TERM...
(Tuesday through Wednesday night)
Issued at 135 AM EDT Mon Aug 18 2025

High pressure will build down the southeastern US coast Tuesday
while Hurricane Erin passes northward offshore, this will lower
precipitation chances across the area. Most of southeast Georgia
will only see isolated to scattered coverage with drier air
infiltrates in, with some higher chances over northeast Florida
where sea breezes interact. Breezy onshore winds will keep the
coast in the mid to upper 80s on Tuesday, with inland highs in the
lower 90s. Wednesday, winds will shift more northerly allowing
high temperatures to reach the low 90s at the coast.

&&

.LONG TERM...
(Thursday through Sunday)
Issued at 135 AM EDT Mon Aug 18 2025

Precipitation chances will begin to increase Thursday through the
weekend as a front pushes southward, then stalls over the area
Friday through Sunday. Numerous showers and thunderstorms will
develop over the area each afternoon and evening.

It`ll be hot Thursday with highs reaching the mid 90s inland, then
temperatures will trend down near normal with increased cloud and
storm coverage Friday and Saturday.

&&

.MARINE...
Issued at 135 AM EDT Mon Aug 18 2025

A surface trough across north Florida will shift south today as high
pressure strengthens north of the region, increasing northeast winds
over the local waters. Swells from Hurricane Erin increase today,
with combined seas reaching Small Craft Advisory thresholds tonight.
Small Craft conditions will continue through Thursday due to
elevated seas as Hurricane Erin tracks northward, east of the U.S.
Atlantic coast through the end of the week.

Rip Currents: High risk today through at least Thursday as long
period swells from Hurricane Erin enter the local waters (periods
14-16 seconds).

A high surf advisory for breakers > 7 ft is still expected Tuesday
through at least Thursday for local beaches. Peak breakers of 8-10
ft are expected Wednesday into Thursday morning. This is when
moderate to localized major beach erosion will be most likely to
occur at local beaches, especially for coastal St. Johns and
Flagler where stronger NNE wind fetch will focus larger surf Wed
evening around high tides.

&&

.HYDROLOGY...
Issued at 135 AM EDT Mon Aug 18 2025

A river flood warning continues for the Altamaha River at Baxley
due to minor flooding, with a fall below flood stage expected
later this morning.

Coastal/Tidal Flood Risk this Week: Latest PETSS and ETSS
guidance indicated inundation to Minor flood stage possible
around high tides along the Atlantic coast during the Wed and Thu
evening high tides - about 1.8 to 2 ft of water inundation
MHHW/AGL datum. The NNE wind fetch will bring lower tidal flood
risk to the St. Johns Basin, but southern sections south of the
river basin from the Buckman Bridge southward toward Racy Point
and Dunns Creek could have inundation of 1-1.5 ft MHHW/AGL datum
given northerly wind fetch. At this time, the above forecast
values would support a Coastal Flood Advisory to possibly be
issued Wed and Thu for minor, nuisance flooding in normally tidal
prone areas. Will continue to monitor tidal inundation forecast
trends.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  93  71  93  73 /  30  10  10   0
SSI  89  77  89  77 /  50  10  20  20
JAX  90  76  92  75 /  70  20  30  20
SGJ  89  78  88  78 /  70  20  40  30
GNV  92  74  93  74 /  70  30  40  10
OCF  92  74  93  74 /  70  40  50  10

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through Thursday evening for FLZ124-125-
     138-233-333.

GA...High Rip Current Risk through Thursday evening for GAZ154-166.

AM...Small Craft Advisory from 2 AM Tuesday to 8 PM EDT Thursday for
     AMZ450-452-454.

     Small Craft Advisory from 8 PM this evening to midnight EDT
     Thursday night for AMZ470-472-474.

&&

$$