Area Forecast Discussion
Issued by NWS Jacksonville, FL

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476
FXUS62 KJAX 101109
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
709 AM EDT Mon Aug 10 2026

.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

- Isolated to Scattered Afternoon and Evening TStorms Today.
  Isolated Storms May be Strong with Gusty Winds, Heavy
  Rainfall, and Frequent Lightning

- Moderate Risk of Rip Currents Today

- Heat and Humidity Builds this Week. Heat Indices Could Briefly
Approach 108 Today. Heat Advisories Possible Each Day from Tuesday
through Friday

&&

.NEAR TERM /THROUGH TONIGHT/...
Main Highlights:

- Scattered Thunderstorms This Afternoon and early Evening.

- Brief Strong Storms Possible, Wind Gusts to near 40 mph and
  locally heavy downpours

- Moderate Risk of Rip Currents at Area Beaches.

Calm to very light south to southeast winds early this morning as
some high cirrus clouds linger with scattered low clouds inland over
the Suwannee Valley and across interior SE GA. The low clouds may
occasionally become broken to overcast before sunrise before
lifting. Very localized fog near areas with heavy rains yesterday is
not expected to expand. Temperatures in the mid 70s to the upper 80s
at the coast and banks of the St Johns river will hold into sunrise.

Today, mean 500 mb ridge will extend from the western Atlantic
waters across the north central FL coast into the the NE Gulf
waters. The surface high will correspondingly stretch across NE FL
and sink into north central FL through today. Low level light
southwesterly flow around the surface ridge axis will prevent much
inland progress of the Atlantic seabreeze to near much past US-17
where the Gulf seabreeze will merge with it in by the mid/late
afternoon hours. Some drier air will lower Precipitable water levels
to near normal values of 1.8-2.0 inches and scattered T`storm
coverage is expected to result along the seabreeze merger with
isolated to widely scattered T`storms as the Gulf and Atlantic
seabreezes move inland and temperatures rise into the lower 90s by
midday to early afternoon hours. Skies will be partly cloudy with
some high cirrus strewn across SE GA much of the day. Southwest
winds 5-10 mph will prevail by late morning, then turn southeasterly
8-12 mph behind the Atlantic seabreeze with gusts to 15 mph at the
beaches. A stronger storm may produce a brief gusty winds 35-45 mph
over NE FL areas east of highway 301 where the seabreezes/outflows
merge, but severe T`storm potential will be low.

Highs will peak in the low to mid 90s along and west of I-95 and
around 90 at the immediate coast. Max heat index values will be
around 104-108 for most locations with some isolated higher values
that could briefly approach 108, but not expecting high enough
values to warrant a heat advisory for today.

Tonight, a few thunderstorms will linger through 8-9PM then quickly
fade with mostly clear skies by midnight under thinning mid and high
level debris clouds. Light southerly winds will turn calm inland and
5-10 mph at the coast, turning southwesterly in the pre dawn early
morning hours. Lows will be slightly above average in the low/mid
70s inland and the upper 70s for the coast.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Main Highlights This Period:

- Daily Isolated to Scattered Afternoon Thunderstorms, some of which
  could be strong

- Increasing Heat Index Values near Heat Advisory levels each day

On Tuesday, the ridge of high pressure will be situated over the
eastern Gulf, through central FL, and into the Atlantic through the
Bahamas and well to the east. This ridge will shift slightly
southward into Wednesday. The position of the ridge is a little south
of the climatology position for August, as a broad low level trough
of low pressure is located along the U.S. east coast from about
Georgia northward.

Overall, lower precipitation chances will be present Tuesday and
Wednesday compared to the past few days, given some drier air in the
lower to mid mid levels and some suppressive affects of a mid level
ridge located just to our south. Nonetheless, deep moisture levels
remain near average levels for this time of year at about 1.9 to 2.1
inches, but some pockets of drier air are located over inland
northeast FL at about 1.6 to 1.8 inches. On Tuesday, prevailing flow
is west-southwest so the west coast sea breeze will be dominate with
the east coast sea breeze making it inland to only the I-85
corridor, but Wednesday the westerly low level flow is a little
stronger and more due west so think that the east coast sea breeze
will not make a whole lot of progress inland. Rain chances on
Tuesday look to be about 20-30 percent, mainly along and north of I-
10, and Wednesday rain chances may be slightly higher, but generally
at 20-40 percent and again preferred chances from I-10 northward,
and along the east coast. The higher end chances over north
zones are due to the better low level moisture located there.
An isolated strong storm with gusty winds remains possible
given DCAPEs approach the 800-900 J/kg range with the MLCAPE of
about 2500 J/kg.

With less cloud cover and storm coverage, highs will be above
normal, climbing into the lower to upper 90s. Max afternoon apparent
temperatures will range from 102-108 degrees, a Heat Advisory may be
needed for some locations either or both days. Can`t rule out some
early morning patchy fog, especially over areas that receive a lot
of rainfall.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Main Highlights This Period:

- Isolated to Scattered Afternoon Thunderstorm Coverage

- Heat Advisory Potential Each Day

Storm chances look lower than normal Thursday, and then trending to
near normal Friday through the weekend.

Prevailing westerly surface winds and increasing mean layer
thicknesses due to the mid level ridge lifting northward into the
the southeast states will yield above normal temperatures. Highs in
the mid to upper 90s are expected, even toward the coastal areas of
southeast GA and northeast FL. Max afternoon heat index values will
approach Heat Advisory criteria near the coast and for some inland
locations.

&&

.AVIATION /12Z MONDAY THROUGH 12Z TUESDAY/...
VFR conditions prevail again with southwest winds 5-8 knots inland
and near 10 knots at the coast turning east to southeasterly 16-18Z
behind Atlantic seabreeze. Seabreeze will help initiate afternoon
thunderstorms with VCTS noted at all sites. High pressure ridge over
the area will limit overall storm chances compared to past few days.

Southerly winds after 00Z with storms ending near the coast and
inland after 01Z under broken mid and high level clouds from fading
storms through the end of the period.

&&

.MARINE...

Atlantic high pressure will gradually build westward across our
local waters today and persist through the week. Southwesterly flow
will prevail over the local waters with an afternoon sea breeze
developing over the near shore waters each afternoon, followed by a
southerly evening wind surge. Winds and seas are forecast to remain
below Caution levels this week. Only isolated afternoon and evening
thunderstorms are forecast today through Friday, mainly impacting
the near shore waters.

Rip Currents: The afternoon sea breeze will combine with a
lingering ocean swell to produce a moderate risk at area beaches
this afternoon. Persistent offshore winds will likely lower this
risk by midweek.

&&

.FIRE WEATHER...
- Patchy High Afternoon Dispersions Beginning Tuesday

Light west to southwest winds will keep the Atlantic seabreeze near
the coast each day, with lower thunderstorm coverage expected today
through Wednesday and forecast to be around 20-40%. A few strong
thunderstorms may produce gusty outflows with locally erratic winds.

Temperatures will rise into the mid 90s inland and lower to mid
90s at the coast today and Tuesday with peak heat index values
rising to heat advisory levels to about 106-110 into midweek.
Dispersions improve gradually today compared to Sunday. Patchy high
inland dispersions expected Tuesday into Wednesday as mixing heights
increase along with increasing westerly transport winds.

Fog Potential: Significant fog development is not expected, with
shallow, patchy fog late overnight limited to areas that receive
locally heavy rainfall.

&&

.CLIMATE...
Daily record high temperatures are possible by Thu-Fri:

Thursday, August 13th:
KJAX: 99/2023
KAMG: 100/9999
KCRG: 96/2023

Friday, August 14th:
KJAX: 99/2023
KGNV: 97/2023
KCRG: 98/2023

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  95  76  95  75 /  10  10  30  20
SSI  92  79  95  79 /  20   0  30  20
JAX  93  75  96  76 /  40  20  30  20
SGJ  92  76  94  76 /  30  10  20  10
GNV  93  74  95  74 /  40  10  10  10
OCF  94  74  95  74 /  20  10  10   0

&&

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

&&

$$