430
FXUS62 KJAX 051253
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
853 AM EDT Sat Sep 5 2026

...New UPDATE...

.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

- Moderate Rip Current Risk Northeast FL Beaches this Weekend

- Daily Heat Index near 105 through the Weekend. Severe Storm Risk
Sunday Afternoon & Evening Southeast GA. Localized Flooding Rain Risk
through Monday

- Patchy Inland Late Night & Early Morning Fog

&&

.UPDATE...
Patchy to areas of fog and low stratus are starting to lift out of
the area. But mostly little change to the ongoing forecast for
today, which shows scattered convection developing through the
late morning mainly over northeast FL, and at times numerous
near the I-75 corridor south of Lake City southeast to Putnam to
Flagler counties. Little changes were made to try to refine the
greater chances of convection later today. Essentially no
change to the forecast tstorms threats/afternoon time frame,
with guidance and observations showing MLCAPE reaching upwards
of about 2000 J/kg, probably a little higher for inland parts of
northeast FL southwest of JAX metro area. This decent instability
along with pockets of some slightly drier air aloft will result
in probably a gustier t-storm wind threat compared to yesterday,
mainly across the south tier of our counties. Probably looking
at wind potential to about 40-50 mph and again heavy rainfall
threat.

Updates were sent with some other minor changes for the sky and
temps.

&&

.NEAR TERM /THROUGH TONIGHT/...
Highlights Through Tonight:

- Isolated/Widely Scattered Thunderstorms, Mainly Over Northeast FL

The area will be under the influence of a very weak pressure
gradient today, as ridging overhead weakens further as a frontal
boundary approaches the area from the north tonight. High pressure
centered to the east/southeast will result in a mainly west to
southwest flow though generally weak around the 5 mph range except
near the coast and St Johns River Basin area where it will be a bit
stronger with a developing sea breeze. This breeze is not expected
to make it much further west that about the I-95 corridor this
afternoon.

With PWATs being lower today (closer to "only" 2 inches") and a bit
of drier air aloft trying to filter into southeast GA, convective
coverage looks to be overall more scattered today, and mainly found
across northeast FL. The vertical profile and setup therefore does
not stand out regarding stronger t`storm potential, though as per
usual with sea breeze convection, isolated gusty downbursts and/or
minor flooding cannot be ruled out, especially where boundary
collisions occur. Light west/southwest flow will result in low 90s
being common across the area today, with some mid 90s possible
across inland GA where lower cloud/storm coverage will be.

Tonight, a few showers streaming off the Gulf in the southwest flow
could make it towards the I-75 corridor at times, with otherwise
daytime convection coming to an end by around the 10pm time frame.
Lows will bottom out in the mid 70s for most.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
Main Highlights This Period: (Sunday through Monday night)

- Localized Flooding Rain Threat

- Isolated Severe Storm Risk Southeast GA Late Sunday

A more dynamic period as a surface front edges southward across the
local area late Sunday into Sunday night, then lingers across
northeast FL Monday bringing more widespread rainfall and the risk
of strong to severe storms. Aloft, a deepening mid level trough
carves southward down the US Atlantic seaboard. The phasing of the
upper level trough over the surface front late Sunday into Sunday
night will bring the risk of a few late day and overnight strong to
severe storms, in what could be an MCS like system, moving from the
northeast over the Carolinas toward the south-southwest toward
southeast GA.

The stronger upper level shear remains to the northeast of the
region, but high surface based instability combined with the cooler
mid level temps, steeping mid level lapse rates and increasing PVA
aloft will bring the risk of gusty downburst winds across southeast
GA Sunday evening through about midnight. At this time, severe storm
risk looks more limited across northeast Florida as the airmass will
have been `worked out` by more typical sea breeze convection earlier
in the day, with a dominant west coast sea breeze regime.

Monday, the surface front is expected to be lingering near the GA-FL
state-line or across northeast Florida as high pressure northeast of
the region begins to wedge southward across north GA. Aloft, the mid
level trough lingers. This pattern could lead to broad surface lows
forming near to just offshore of the local Atlantic coast for the
early part of next week within an inverted coastal trough. Waves of
gusty coastal showers and isolated storms will move onshore and
expand in coverage as they shift inland with daytime heating into
Monday afternoon toward the I-75 corridor into Monday evening.

Monday night, the ridge to the northeast expected to settle farther
southward, with strengthening NNE to ENE winds along the coast into
Tuesday morning and continuing coastal showers and isolated storms
overnight as the surface front is shunted a little farther south
toward north-central Florida.

The Weather Prediction Center maintains a Marginal Risk (level 1 out
of 4) of localized flooding rainfall both Sunday and Monday across
the local area. In addition, the Storm Prediction Center has a
Marginal Risk of severe storms for southeast GA Sunday evening
(level 1 out of 5).

Temperatures will top out in the low to mid 90s Sunday before
showers and storms ensue with heat index values topping out near 105
degF, just below local Heat Advisory criteria. Monday, cooler with
onshore easterly flow with highs in the 80s for most locations to
near 90 toward the I-75 corridor due to clouds cover and convection.
Lows will range in the 70s each night.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Main Highlights This Period: (Tuesday through Saturday)

- Breezy Onshore Winds Tuesday & Wednesday,

- Warm-Up Late Week

- Daily Thunderstorms Chances

- Elevated Tidal Levels with Approach of Sept 11 New Moon

Breezy northeast to east winds Tuesday and Wednesday as the coastal
trough lingers over the adjacent coastal waters. This will bring
coastal showers and isolated storms onshore, with coverage expanding
inland each afternoon into the early evening across inland areas
with diurnal instability. Aloft, the upper level trough axis shifts
downstream and weakens with more stable conditions aloft favoring a
lower severe storm risk. Thursday into Friday the surface high
builds east then southeast of the region, with a return of westerly
steering flow across the local area and a more dominant west coast
sea breeze regime. Temperatures warm as highs rebound back into the
lower 90s, just above climo values. Friday into Saturday, extending
models are showing another front approaching from the north, but
differ on the timing and mid level synoptic features. At this time,
NBM consensus favors the front edging southward across the area late
Friday into Saturday, with a return of easterly flow by Saturday
with scattered showers and storms.

&&

.AVIATION /12Z SATURDAY THROUGH 12Z SUNDAY/...
Main areas of low cigs or vsby restrictions are from about I-10
northward so affecting VQQ, JAX, and SSI terminals. Expect some
period of IFR and LIFR for these terminals through about 14z. Lower
chance of any cig or vsby issues for SGJ and GNV, and CRG early this
morning. Cigs should lift out mid morning but some MVFR cig
probabilities remain 14z-16z. Will again see fairly quick
development of showers and storms, but mainly for the northeast FL
area today. Good chances expected for SGJ and GNV, with slightly
lower chances for the Duval county terminals. May able to only show
just VCSH or a VCTS for SSI where the chances are much lower
compared to northeast FL. Expect fairly quick-end to convection by
about 23z/00z. Some patchy fog and low stratus possible again early
Sunday morning, but does not look to be widespread or quite as much
as this morning so may only show MVFR cigs or vsby, at best, for
now. Sfc winds will be west to southwest about 5-10 kt later today,
with sea breeze wind shift probably for SGJ and SSI this afternoon.

&&

.MARINE...


Weak high pressure will remain in place through tonight before a
frontal boundary sinks south across area Sunday through Monday
night. High pressure will build to the northeast following the front
early next week with a coastal trough over the local waters.
A brief period of Small Craft Exercise Caution conditions is
possible mainly over the Georgia waters Tuesday. The trough weakens
mid- week as high pressure builds south of the region. Another front
approaches from the north early next weekend.

Rip Currents: Rip current risk will remain moderate across
northeast FL beaches through the weekend with lingering long period
swells and a developing onshore flow each afternoon and evening. The
risk will be slightly lower at southeast GA beaches.

&&

.FIRE WEATHER...
- Patchy Low Dispersions Ne Fl Monday

West to southwest winds this weekend will bring a more dominant west
coast sea breeze across the area. Morning showers and isolated
storms will begin to move inland form the Gulf, with rainfall
expanding in coverage into the afternoon and early evening across
inland areas toward the Atlantic coast where the east coast sea
breeze will be near the Interstate 95 corridor to the coast. There
is a risk of stronger to severe storms late Sunday into Sunday night
across southeast Georgia as a front moves into the area. The front
is expected to linger across northeast Florida Monday, which will
create low daytime dispersion, more cloudiness and bring elevated
rain chances through the day. Winds will transition to northeast
along and north of the front Monday.

Fog Potential: Gusty and erratic winds will occur with thunderstorm
activity. Patchy inland morning fog each day.

&&

.HYDROLOGY...
Coastal water levels begin to increase next week with the approach
of the New Moon on Sept 11th and breezy onshore easterly winds late
Monday through Wednesday, with the peak winds across the local
waters and coast Tuesday. At this time, extended probabilistic
guidance keeps water levels below action stage late Tuesday through
Wednesday both along the local Atlantic coast and within the St.
Johns River basin.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  92  75  95  73 /  20  20  70  80
SSI  91  77  93  75 /  10  20  60  80
JAX  91  75  93  74 /  30  20  50  60
SGJ  90  76  93  75 /  50  20  60  60
GNV  90  74  92  73 /  60  10  40  50
OCF  90  74  92  74 /  60  10  50  40

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
MARINE...None.

&&

$$