843
FXUS62 KJAX 301143
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
743 AM EDT Tue Sep 30 2025

...New UPDATE, AVIATION...

.KEY MESSAGES...

For the latest NE FL and SE GA Daily Key Messages please visit:
https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf

- Tropical Storm Imelda Local Impacts This Week. High Risk of Rip
  Currents, High Surf & Small Craft Advisory through Friday.
  Minor Coastal Flooding Possible Thursday through the Weekend.
  Monitor forecasts at hurricanes.gov

- Increased Chances of Showers/Storms Friday through Sunday.
  Multiple rounds of showers and a few storms. Locally heavy
  rainfall/flooding rain possible for coastal areas

&&

.UPDATE...
Issued at 732 AM EDT Tue Sep 30 2025

Forecast remains on track as Breezy to Windy North to Northeast
flow will keep mostly cloudy skies in place along with the risk of
coastal showers that will press inland through the afternoon. Max
temps will remain below normal will highs around 80F along the
Atlantic Coast and into the middle 80s further inland. Main
impacts will be the high surf, high rip current risk and beach
erosion at the NE FL/SE GA beachfront locations, along with solid
SCA and occasional gale force wind gusts over the Marine waters.
For now still expect peak wind gusts in the 30-40 mph along the
Atlantic beachfront locations and will hold off on any Wind
Advisory issuance for now, but will be monitoring through the
afternoon hours.

&&

.NEAR TERM...
Issued at 209 AM EDT Tue Sep 30 2025

Tropical Storm Imelda, currently just north of the Bahamas, will
gradually strengthen into a hurricane as it shifts east-
northeastward further into the western Atlantic. With strong high
pressure building down the eastern US and TS Imelda, the tight
local pressure gradient maintains breezy northerly winds with
gusts of 15-20 mph inland and around 30 mph along the coast. Drier
air advects in from the north lowering PWATs to the 1.3-1.6 in.
for inland areas. Skies will begin mostly cloudy and trend more
partly cloudy as drier air begins to filter into the area as
Imelda`s circulation draws in more continental air into the region
as it exits away. With the drier air, rain chances will be
confined to along and east of the I-95 corridor as rounds of
isolated/scattered coastal showers with embedded storms shift
onshore through the day. Highs will be coolest at the coast in the
low 80s due to the northerly flow and warm into the mid/upper 80s
west of highway 301. The drier air will allow for cooler lows in
the mid 60s over inland SE GA, upper 60s over inland NE FL west of
the St Johns river and coastal SE GA and low 70s over coastal NE
FL.

&&

.SHORT TERM...
(Wednesday through Thursday night)
Issued at 209 AM EDT Tue Sep 30 2025

An area of strong high pressure located over eastern Canada will
slip southward this period and moving to a position in the Mid
Atlantic states by late Thursday night. Aloft, broad low pressure
at 500 mb is located from the Gulf Coast to the southeast states.
Daintily for Wed, we see Imelda scooting quickly eastward while
the ridge of high pressure arches down into the deep south. As
Imelda moves out of the picture, the northeast flow regime begins
to intensify as some broad low pressure remains across the
southern Gulf and the northwest Caribbean. Some shower activity
will be possible for the coastal areas of northeast FL on Wed
mainly southeast zones, and then increases gradually into Wed
night through Thu night as moisture increases on the breezier
northeast flow. Northeast winds of 15-25G35 mph and gusty expected
coastal areas (and St Johns River Basin) on Wednesday. Winds may
be a bit higher on Thursday, with wind advisory potential, for
gusts of about 40 mph. Inland zones have winds more in the 10-20
mph range with gusts up to 30 mph. Rainfall amounts light for the
Wed-Wed night time frame but may pick up a bit Thu to Thu night as
low level convergence and bands of showers increase. Temps both
days in the 80s, with a cooler trend on Thu due to winds
increasing and potential for more cloudiness. With the onshore
flow prevailing, the coast will be warmer at night than inland
with lows coast lower to mid 70s but inland southeast GA/northeast
FL able to drop to lower to mid 60s.

&&

.LONG TERM...
(Friday through Monday)
Issued at 209 AM EDT Tue Sep 30 2025

The strong high pressure over the Mid Atlantic area will slowly
shift eastward into the Atlantic this period while aforementioned
low pressure trough/low aloft over the Gulf coast begins to
support some surface low development in the central Gulf. A fairly
long fetch of deep easterly flow is pointed toward Florida on
Friday with PWATs of about 1.5 to 1.8 inches over our forecast
area. Over the weekend, deep layer flow begins to veer to east
and southeast with coastal surface troughing and low level convergence
anticipated. This different regime will draw up additional moisture
from the south with PWATs rising to 2 inches and possibly higher.
This should support an unsettled weather pattern for the weekend
with showers and embedded t-storms causing heavy downpours/localized
flooding concerns, especially for the eastern zones.

For the coastal areas from Friday through Monday, preliminary
rainfall amounts of 3-5 inches are possible, with 1-3 inches
inland. Localized higher amounts to about 6 inches possible for
the coast. This would certainly cause some minor flooding concerns
especially for urban areas and poor drainage. Probability of about
3 inches or more for the coastal areas for Friday morning through
Monday morning is progged at about 20-30 percent.

Highs in the lower to mid 80s are forecast and lows from mid 60s
to lower to mid 70s. Possible the highs will be more muted due to
clouds and precipitation.

&&

.AVIATION...
(12Z TAFS)
Issued at 732 AM EDT Tue Sep 30 2025

Widespread MVFR CIGS at NE FL terminals and IFR CIGS at SSI will
continue this morning along with increasing gusty North winds to
15G25 knots and rainfall chances for the coastal terminals. Some
lifting of CIGS is expected this afternoon, but will remain at
MVFR levels for all terminals except for GNV where some CIGS could
improve briefly into the VFR range around 3500 ft. MVFR CIGS
linger tonight after sunset with slow decrease in wind speeds to
around 5 knots at inland TAF sites, but will remain elevated
around 10 knots at the coastal terminals. Some improvement to VFR
levels is possible at SSI late in the TAF period, but for now have
kept MVFR CIGS in place.

&&

.MARINE...
Issued at 209 AM EDT Tue Sep 30 2025

Small Craft Advisory conditions with breezy north-northeasterly
winds and high seas will persist across the coastal waters through
the week. The area will be between Tropical Storm Imelda lifting
away from the Florida east coast and strong high pressure building
down the eastern US. Winds shift to easterly Friday into the weekend
as the strong high pressure shifts further down the eastern
seaboard.

Rip currents: Increasing swells from Imelda and Humberto will
lead to high rip current risk today and continuing through much of
the week.

Surf: Surf continues to build today and reaches into the 8-12 ft
range today into Thursday. Surf will be slow to subside this
week.

&&

.HYDROLOGY...
Issued at 209 AM EDT Tue Sep 30 2025

Coastal flooding potential: Lingering high seas, developing
onshore flow and the approaching full moon cycle will lead to
potential minor tidal flooding for Thursday into the weekend.
Current forecasts show up to about 2 ft MHHW at the coast and 1-2
ft MHHW for the St Johns River Basin and Intracoastal Waterway.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  83  63  85  62 /  40  20   0   0
SSI  80  68  81  71 /  50  20   0  10
JAX  81  67  84  69 /  50  20  10  20
SGJ  82  71  83  72 /  70  40  20  40
GNV  85  67  88  69 /  30  20  10  10
OCF  86  68  87  70 /  30  20  10  10

&&

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

     High Surf Advisory until 2 AM EDT Friday for FLZ124-125-138-233-
     333.

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

     High Surf Advisory until 2 AM EDT Friday for GAZ154-166.

AM...Small Craft Advisory until 8 PM EDT Friday for AMZ450-452-454-
     470-472-474.

&&

$$