173
FXUS62 KJAX 071856
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
256 PM EDT Tue Oct 7 2025

...New NEAR TERM, SHORT TERM, LONG TERM, AVIATION, MARINE, HYDROLOGY...

.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

- Mostly Minor Tidal Flooding Continues within the St. Johns River
  Basin and along the coast through Wednesday Evening.

- Significant Coastal / Tidal Flood Event Develops on Thursday and
  Friday as Strong Onshore Winds Overspread Our Area. Coastal
  Flood Watches are Likely for Thursday and Friday all along the
  Atlantic Coast and within the St. Johns River Basin.

- Heavy Downpours and Embedded Thunderstorms Possible on Thursday
  and Friday Along the I-95 Corridor, with Localized Flooding
  Possible, Especially During Times of High Tide.

&&

.NEAR TERM...
(Through Tonight)
Issued at 245 PM EDT Tue Oct 7 2025

Surface high pressure ridge over the southeast states will weaken
through tonight while the low level flow continues to be easterly.
The flow should weaken and there won`t be as much low level convergence
as we have seen in the past day or so. This pattern, along with
some drier air filtering from the east, will lead to lower chances
of showers by tonight. Can`t rule out a lone shower but after
after about 8-9 PM, shower chances are less than 15 percent. But,
for the rest of this afternoon, isolated to scattered shower activity
expected to continue into the evening hours and should largely
dissipate by 8 PM. After about 3 AM, some low stratus and patchy
fog, possibly locally dense mainly across inland southeast GA.
Otherwise, lows in the mid 60s inland, to the lower 70s coast with
skies becoming mostly clear except for inland southeast GA where
stratus may become dominant cloud cover.

&&

.SHORT TERM...
(Wednesday through Thursday night)
Issued at 245 PM EDT Tue Oct 7 2025

Mid/upper level ridging will slide west of the region as a potent
shortwave trough moves from the eastern Great Lakes/Upper OH valley
into the NE and Mid Atlantic region. Weak surface pressure pattern
expected ahead of the cold front as high pressure shifts far into
the Atlantic waters ENE of the region and weak coastal troughing
moves onshore and weakens with a few light coastal showers to start
the day. The front approaching from the NW may kick off isolated
showers closer to the Altamaha river basin north of Waycross, but
otherwise light winds will prevail 10-15 mph over NE FL/5-10 mph
over SE GA. Skies will be partly cloudy with Atlantic cumulus
moving onshore underneath increasing cirrus clouds aloft as jet
stream level winds increase ahead of the approaching trough. Highs
will be coolest along the coast in the low/mid 80s and warm to
the upper 80s west of I-95.

Wednesday night, the cold front will enter SE GA with isolated to
scattered showers persisting overnight north of US 84. Winds will
become northeasterly and increase in the predawn morning hours
Thursday from near calm to 5-10 mph, gusting to 15 mph near the
Altamaha river. Lows will be above normal in the upper 60s inland
to the low 70s along the coast and around 70 over inland north
central FL.

Thursday, mid/upper level trough deepening over New England will
extend a ribbon of shortwave energy back into the TN river valley
that will shift towards the area into Thursday night. The upper
level support will drag a cold front through much of the area on
Thursday. Meanwhile, strong ridging aloft will extend from Quebec
into the Appalachians behind the deepening trough and allow for
strong high pressure to wedge southward from the St. Lawrence
Valley into Mid Atlantic and Carolinas, increasing the local
pressure gradient. As the high builds down, a coastal trough will
begin to develop behind the cold front with scattered to numerous
coastal showers developing and pushing onshore. Some isolated to
scattered embedded T`storms in convergent showers. While not
expecting very strong 0-6km shear more than 20-25 knots, colder
temperatures aloft around -10 to -11 C will support stronger
updrafts and a few isolated T`storms may become strong and
produce locally heavy downpours and gustier winds around 40 mph.

Winds Thursday will be highest at the coast 15-25 mph with gusts
to 35-40 mph, 15-20 mph along the St Johns river gusting to 35 mph,
and 10-15mph gusting to 30 mph further inland. Skies will be mostly
cloudy with highs only reach the upper 70s over portions of SE GA
near the Altamaha river and the SE GA coast, low 80s along the
NE FL coast and mid to upper 80s over the I-75 corridor of NE FL.

Thursday night, the coastal trough will strengthen as the ribbon
of shortwave energy upstream over GA develops into a compact,
closed shortwave trough. This will enhance lift and numerous
coastal showers will push onto the NE FL coast to I-95 overnight
into early Friday with ongoing breezy winds 15-20 mph with gusts
to 30-35 mph. Away from the coast, drier air at the surface will
filter in from the north and lows will fall to around 60 degrees
across inland SE GA with a sharper onshore flow keeping lows in
the low 70s at the NE FL coast.

&&

.LONG TERM...
(Friday through next Tuesday)
Issued at 245 PM EDT Tue Oct 7 2025

The period will begin with a wet and windy pattern at the coast
as a closed shortwave trough will hover near the FL and GA coast.

Strong ridging aloft will follow a trough departing east into the
western Atlantic waters and will support strong high pressure near
the New England coast Friday into Saturday. Strong flow between the
high to the NNE and developing coastal low over the waters will
generate breezy to near windy conditions at the local beaches to
the I-95 corridor with gusts sustained 15-25 mph winds and gust
to around 40 mph in these locations, dropping off only slightly
inland to 10-15 mph gusting to 30 mph well away from the coast.
Numerous coastal showers expected Friday to move onto the I-95
corridor of NE FL, becoming more scattered coverage by Saturday
as the coastal low begins to lift north, paralleling the Carolina
coast while areas west of highway 301 will only see limited
isolated showers Friday and dry conditions Saturday. Rainfall
totals along the coast through Sunday morning along and east of
I-95 will be 1-2 inches with locally higher amounts supported
by the 90th percentile NBM to be 3-5 inches for most coastal
communities with 4-6 inches for coastal Flagler county.

Drier conditions arrive Sunday into early next week as another
upstream trough slides south and east from the Great lakes and
help to open and lift the compact shortwave northward from the
Coastal Carolinas to the Mid Atlantic coast with dry northwest
flow aloft as ridging in the mid/upper levels will shift east
into the Western Gulf early next week. Surface high pressure
will persist near the FL panhandle with light northerly
winds inland to northeasterly closer to the NE FL coast.

Temperatures will begin the period below normal with highs in
the 75-80 degree range Friday and Saturday and slowly rising to
near normal by Tuesday into the low 80s. Lows will begin near
normal in the 60-65 degree range inland/65-70 degrees Friday
night and then go below normal Saturday night through Monday
night 55-60 inland/60-65 degrees at the coast.

&&

.AVIATION...
(18Z TAFS)
Issued at 245 PM EDT Tue Oct 7 2025

Occasional MVFR vsby/cigs continues due to the isolated to
scattered shower activity and potentially a rumble of thunder
over the next few hours. The frequency/probability of MVFR should
drop considerably by 23z-00z with mostly VFR overnight. However, some
chance of MVFR at JAX and GNV, but high enough to have a prevailing
MVFR vsby for VQQ late tonight. Sfc winds this aftn will be sustained
easterly about 8 to 13 kt and will drop to 7 kt or less after
00z.


&&

.MARINE...
Issued at 245 PM EDT Tue Oct 7 2025

Easterly flow at about 15 kt or so expected to continue into Wed night
with some gradual weakening possible as the gradient diminishes.
We should see markedly higher winds on Thursday and Thursday night
as a cool frontal boundary moves through and the gradient fairly
rapidly strengthens. We could see gale force gusts as early as Thu
aftn but more so by Thu night or Friday as the gradient is moderate
to strong with the high pressure ridge to the north and lower pressure
troughing across far south toward the FL straits. Based on latest
NWPS wave forecasts, seas are near or just over 8 or 10 ft over
majority of the waters Thu night. Peak in wave heights, in the
10-15 ft range, look to occur generally from late Friday night
into Saturday night.

Rip current: Moderate to high rip current risk continues with the
highest risk more over the northeast FL beaches into Wed with
rough surf and deadly rip currents.

&&

.HYDROLOGY...
Issued at 245 PM EDT Tue Oct 7 2025

Water levels continue to meet minor flood levels along the Atlantic
coast from Duval county southward and within the Intracoastal
Waterway (ICCW), and the St Johns River Basin so a coastal flood
advisory remains in effect. Water levels are peaking at about 1.6
to 1.95 feet MHHW and don`t see much change into Wednesday.
Therefore, the advisory was extended out into Wed evening at this
time. The earlier coastal flood warning for Putnam county was
downgraded based on the observations and trends.

Prior discussion...the lull in tidal flooding will be short- lived,
as astronomical influences from today`s "Supermoon" set up a
significant coastal and tidal flood event later this week and into
the upcoming weekend as a surge of strong northeasterly winds
overspreads our area. This event has the potential to bring the
highest tidal levels that we have seen along the Atlantic coast
and within the St. Johns River basin thus far this Fall, and a Coastal
Flood Watch will likely be issued by Wednesday in anticipation of
widespread moderate tidal flooding that should begin during high
tide cycles from Thursday afternoon through the upcoming weekend.

Strong onshore winds will likely bring another round of high surf
advisories and the potential for even more significant beach
erosion all along the Atlantic coast by Friday and the upcoming
weekend, along with a high risk of deadly rip currents.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  66  87  68  78 /  10  10  20  20
SSI  71  83  70  79 /   0  10  10  40
JAX  69  87  70  82 /   0  10  10  50
SGJ  73  85  73  83 /   0  10  10  50
GNV  68  90  69  85 /   0  10  10  30
OCF  68  89  71  85 /   0  10  10  20

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Coastal Flood Advisory until 8 PM EDT Wednesday for FLZ038-125-
     132-137-138-225-233-325-333-633.

     High Rip Current Risk through late Wednesday night for FLZ124-
     125-138-233-333.

GA...High Rip Current Risk until 8 PM EDT this evening for GAZ154-166.

AM...Small Craft Advisory until 5 AM EDT Wednesday for AMZ452-454-472-
     474.

     Small Craft Advisory until 5 PM EDT this afternoon for AMZ470.

&&

$$