328
FXUS62 KJAX 081142
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
742 AM EDT Wed Oct 8 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

- Minor Tidal Flooding Continues Through Wednesday evening.
  Coastal Flood Advisory: Minor Tidal Flooding along Northeast FL
  coast, ICWW, and the Rest of the St. Johns River Basin

- High Rip Current Risk Continues at the Northeast FL Beaches

- Long Duration Nor`easter Develops on Thursday. Strengthening
  Northeasterly Winds Thursday Bring Widespread Moderate Tidal
  Flooding. Coastal Flood Watches are Likely for the Atlantic
  Coast and St. Johns River Basin. Gale Watches Posted for the
  Atlantic Waters from Thursday Afternoon through Sat Night. High
  Surf & Wind Advisories Likely for Coastal Locations Thursday
  through Friday. Heavy Downpours and Isolated Thunderstorms Along
  the I-95 Corridor Thurs & Fri. Destructive Beach Erosion
  Possible at Area Beaches through the Weekend

&&

.UPDATE...
Issued at 728 AM EDT Wed Oct 8 2025

Forecast on track with fairly quiet conditions today ahead of
strong cold frontal passage and local Nor`Easter conditions
expected on Thursday. Expect the warmest day of the week today as
Max temps reach into the upper 80s/near 90F over inland areas,
while middle 80s expected along the I-95 corridor and Atlantic
Coastal areas. NE flow and inland moving East Coast sea breeze may
still be enough to trigger a slight chance of a shower during peak
heating today, but overall rainfall chances remain 20 percent or
less across NE FL and coastal SE GA, while a pre-frontal trough
pushing into inland SE GA later this afternoon and evening may be
enough to trigger scattered showers and an isolated storm, but
overall storm threat remains low at this time.


&&

.NEAR TERM...
Issued at 328 AM EDT Wed Oct 8 2025

Near calm winds early this morning and lingering low-level
moisture may be enough for patchy fog to develop over inland
locations, with locally dense fog possible for locations in SE GA.
Current satellite obs depicts PWAT values of 1.40"-1.65" over the
area as dry air will continue to shift into the area. The drier
air aloft will bring lower coverage of showers Today, though there
could still be a few light showers as the onshore flow may bring
in a few showers towards coastal locations near and south of St.
Augustine. A cold front will begin to approach SE CONUS Today,
nearing northern SE GA during the overnight hours into Thursday.
Isolated to scattered showers may develop ahead of the front by
the late afternoon to early evening hours. Showers are expected to
persist through the overnight hours in Thursday morning as the
front pushes into SE GA. Marine winds will begin to increase as
the front begins to shift over the local waters.

Otherwise, highs will once again be in the 80s area-wide with
upper 80s for locations west of the I-95 corridor and in the lower
80s along the coast. Lows on Wednesday night in the upper 60s for
locations across inland SE GA and the Suwannee Valley Region of NE
FL, while lower 70s along the coast and the rest of inland NE FL.

&&

.SHORT TERM...
(Thursday through Friday night)
Issued at 328 AM EDT Wed Oct 8 2025

A longwave trough will deepen over the eastern third of the nation
on Thursday, driving a cold front southward across our region.
Meanwhile, a potent shortwave trough digging east-southeastward
from the Ozarks through the Tennessee Valley will deepen and
cutoff over the southeastern states by Friday morning. Otherwise,
a strengthening surface ridge (around 1035 millibars) will build
over the eastern Great Lakes in the wake of this frontal passage,
with this feature shifting eastward over New England by Thursday
night and wedging down the southeastern seaboard as coastal
troughing redevelops and sharpens over our local Atlantic waters.
Coastal convergence will strengthen once the frontal boundary
slips southward across north central FL on Thursday afternoon and
evening, resulting in increasing shower coverage along the I-95
corridor. Cooling temperatures aloft may also support isolated,
mainly elevated convective development over the Atlantic waters on
Thursday, with this activity potentially moving onshore along the
I-95 corridor by Thursday afternoon and evening.

The big weather story on Thursday and Thursday night will be
steadily increasing onshore winds, as our tightening local
pressure gradient creates wind speeds of 20-30 mph by the early to
mid afternoon hours at coastal locations, with breezy conditions
spreading inland as the day progresses. Wind gusts of 35-45 mph at
coastal locations will introduce potential Wind Advisories along
the I-95 corridor by Thursday afternoon and evening. Increasing
cloud cover, rain chances, and onshore winds will keep highs in
the upper 70s across southeast GA, lower 80s for northeast FL, and
mid 80s for north central FL, where the front will likely not move
through until later in the afternoon.

Coverage of showers and a few embedded, mainly elevated
thunderstorms is expected to increase along the I-95 corridor on
Thursday afternoon and evening, with activity potentially
persisting into the overnight hours as a sharpening coastal trough
and strong onshore winds result in strong coastal convergence.
Locally heavy rainfall will be possible, with training bands
potentially setting up over portions of coastal northeast FL that
may present a localized flood threat, particularly if heavy
downpours coincide with high tide. Cool air advection in the wake
of the front will drive lows on Thursday and Friday nights down to
near 60 for inland portions of southeast GA, with 60s elsewhere,
except around 70 for north central and coastal northeast FL.

Troughing will continue to cutoff from the main flow over the
southeastern states on Friday, yielding cyclogenesis along the
frontal boundary east of Cape Canaveral by Friday evening.
Meanwhile, strong high pressure centered over New England will
gradually weaken and shift eastward by Friday night as this low
pressure center takes shape over the Gulf Stream waters adjacent
to our region. This weather pattern will maintain a very tight
local pressure gradient across our area, and a drier air mass will
advect across inland southeast GA and the Suwannee Valley by
Friday afternoon. Strong coastal convergence will keep a threat
for heavy rainfall in place along the I-95 corridor on Friday.
Strong onshore winds will combine with lingering high astronomical
tides from this week`s full "Harvest" Moon to produce significant,
potentially widespread moderate to major coastal flooding along
the Atlantic coast and within the St. Johns River basin (see
"Hydrology" section below for details). Cloud cover and cool air
advection will keep highs in the 70s on Friday, except around 80
for north central FL.

&&

.LONG TERM...
(Saturday through Tuesday)
Issued at 328 AM EDT Wed Oct 8 2025

A deepening low pressure center will lift slowly northward
along the Carolina Coast on Saturday, becoming stacked
in tandem with the cutoff trough aloft near the Outer
Banks on Saturday night. North-northeasterly winds will
remain breezy at inland locations and windy at the coast,
with wrap-around showers likely along the I-95 corridor
through around noon on Saturday. A much drier air mass
will then overspread our region on Saturday night and
Sunday as winds shift to northerly with gradually
decreasing speeds. Cloud cover and gusty winds will keep
highs on Saturday in the upper 70s for locations along
and east of U.S. Highway 301, with partial sunshine on
Sunday afternoon allowing highs to reach near 80 further
inland. Clearing skies on Saturday night will allow lows
to fall to the mid and upper 50s at most inland locations,
while a northerly breeze keeps coastal lows in the low
to mid 60s.

The non-tropical or hybrid gale center off the Carolina
coast will likely become stationary late this weekend
and early next week, keeping a funnel of seasonably cool
and dry air over our region, compliments of deep
northwesterly flow aloft. A dry air mass and plenty of
sunshine will allow highs to climb to the lower 80s inland
on Sunday, with coastal highs likely remaining in the
upper 70s. Heights aloft will then rise by Tuesday and
Wednesday as ridging aloft expands from Texas eastward
along the northern Gulf coast, allowing for highs to
slowly climb to the low to mid 80s inland, while breezy
onshore winds keep coastal highs around 80. Nighttime lows
will continue to fall to the 55-60 range inland, while an
onshore breeze keeps lows in the mid 60s at coastal
locations.

&&

.AVIATION...
(12Z TAFS)
Issued at 728 AM EDT Wed Oct 8 2025

LIFR conds at SSI in low stratus early this morning that should
fade after 13Z, otherwise VFR conds at the NE FL terminals and
while some brief MVFR CIGS are possible this morning in diurnal
heating, rainfall chances remain low enough to leave out of all
terminals as NE winds slowly increase close to 10 knots along with
scattered fair weather Cu in the 3000-4000 ft range through the
afternoon hours. Light winds to begin tonight, then slowly
increase late in the TAF period, mainly at SSI as the frontal
boundary approaches with potential MVFR CIGS and VCSH after 10Z,
otherwise the usual patchy MVFR fog at VQQ from 06-10Z late
tonight.

&&

.MARINE...
Issued at 328 AM EDT Wed Oct 8 2025

Seas will begin to subside to around 4-6ft with Small Craft
Exercise Caution levels for most of the local waters by this
morning as winds also dip to 10-15 knots. With an approaching
frontal boundary to the local waters, winds and seas are expected
to rise once again to Small Craft Advisory conditions by Thursday
Morning. Gale force gusts will develop by mid to late Thursday
afternoon as the local gradient strengthens as the front moves
across the local waters. Gale Watches have been posted beginning
on Thursday afternoon both near shore and offshore, and strong
northeasterly winds overspread our region. Hazardous boating
conditions are expected to continue into the weekend as an area of
low pressure develops offshore of the FL peninsula and shifts
northward towards the Carolina Coast.

Rip current: Moderate to high rip current risk continues today
with the highest risk more over the northeast FL beaches with
rough surf and deadly rip currents. Increasingly dangerous, rough
surf conditions developing on Thursday will expand the high risk
to all area beaches that will persist this weekend and possibly
into next week.

&&

.FIRE WEATHER...
Issued at 328 AM EDT Wed Oct 8 2025

Northeasterly surface and transport winds will prevail area-wide
today. Breezy transport speeds are expected for locations south
of I-10 this afternoon, with breezy surface speeds developing
at coastal locations. These winds and elevated mixing heights at
inland locations will yield fair to good daytime dispersion
values area-wide today. Northeasterly surface and transport
winds will then steadily strengthen shortly after sunrise on
Thursday, with strong and gusty surface speeds developing by the
late morning or early afternoon hours at coastal locations. These
strong winds will counter increasing cloud cover and rain chances,
creating good daytime dispersion values for coastal southeast GA
and northeast FL, with marginally high values possible across
north central FL. Fair values are forecast across inland southeast
GA. Strong northeasterly surface and transport winds will persist
at coastal locations on Thursday night and Friday nights, creating
elevated nighttime dispersion values along the I-95 corridor. A
drier air mass will begin to filter into inland southeast GA and
the northern Suwannee Valley on Friday, where only isolated showers
are forecast. Breezy northeasterly surface and transport winds will
result in fair daytime dispersion values. Strong northeasterly
surface and transport winds will prevail elsewhere, again yielding
good daytime dispersion values.

&&

.HYDROLOGY...
Issued at 328 AM EDT Wed Oct 8 2025

Water levels continue to meet minor flood levels along the Atlantic
coast from Duval county southward and within the Intracoastal
Waterway (ICWW), and the St Johns River Basin so a coastal flood
advisory remains in effect. Water levels are peaking at about 1.5
to 2 feet above Mean Higher High Water during times of high tide.

A significant, long duration coastal and tidal flood event will
unfold from Thursday afternoon through the 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
later today in anticipation of widespread moderate tidal flooding
that should begin during high tide cycles from Thursday afternoon
through the upcoming weekend. Latest Probabilistic Extra-tropical
Storm Surge (PETSS) guidance indicates that water levels may peak
in the 2.5 - 3.5 foot range above MHHW along the Atlantic Coast
during the high tide cycle around noon on Friday and during the
early afternoon on Saturday`s high tide cycle, which would
approach Major flood thresholds. Moderate flooding appears to be
likely within the St. Johns River basin, where water levels will
likely peak in the 2-3 foot range above MHHW during times of high
tide this weekend.

Strong onshore winds will likely bring High Surf Advisories and
the potential for destructive beach erosion all along the
Atlantic coast by Friday and the upcoming weekend.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  89  67  77  59 /  40  50  20  10
SSI  83  71  78  65 /  20  50  50  50
JAX  87  70  81  66 /  20  30  60  50
SGJ  85  72  82  70 /  40  20  60  70
GNV  90  69  85  67 /  20  20  30  30
OCF  89  69  85  70 /  20  10  30  20

&&

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

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

GA...None.
AM...Small Craft Advisory from 8 AM to 2 PM EDT Thursday for AMZ450-
     470.

     Gale Watch from Thursday afternoon through Saturday evening for
     AMZ450.

     Small Craft Advisory from 11 AM to 5 PM EDT Thursday for AMZ452-
     454-472-474.

     Gale Watch from Thursday afternoon through late Saturday night
     for AMZ452-454-472-474.

     Gale Watch from Thursday afternoon through late Saturday night
     for AMZ470.

&&

$$