764
FXUS62 KJAX 131758
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
158 PM EDT Thu Aug 13 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

- Oppressive Heat & Humidity Continues Area -Wide. For Today and
Friday, Extreme Heat Warning for Coastal Southeast GA and. Daily Heat
Advisories Likely Continue for Much of Our Area into Next Week

- A Few Strong Thunderstorms this Afternoon/Evening & Friday.
  Scattered Thunderstorms Today and Friday. Isolated Damaging
  Wind Gusts of 40-55 mph, Frequent Lightning Strikes & Heavy
  Downpours are Possible

- Daily Scattered Afternoon & Evening TStorms Friday through Tues

&&

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

- Extreme Heat Warning and Heat Advisories in Effect Rest of Today

- A Few Strong thunderstorms this Afternoon and Evening. Stronger
Storms Will Be Capable of Producing Strong Wind Gusts, Frequent
Lightning Strikes, and Torrential Downpours.

Dangerously hot temperatures continue this afternoon through around
sunset, with a Heat Advisory in effect for all but the southeast
Georgia coast, where an Extreme Heat Warning is in effect through
8pm. High temperatures will range from the mid to upper 90s, with
max afternoon heat indices reaching 108-114 degrees.

Overall, highest rain and storm chances are south of Jacksonville
this afternoon and evening, with convective models highlighting the
Putnam/Marion/Flagler area for isolated strong storm development.
Plenty of surface based instability will be present, with DCAPE
forecast to be near 1,000 J/kg in that region, posing a gusty wind
threat with any strong storm development. The main limiting factors
for more convection is the suppression effects of the ridge aloft to
our west and lower amounts of low level moisture, especially over
inland southeast GA. Convection will generally simmer down around
sunset tonight.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Main Highlights This Period:

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

- Heat Index Values near Heat Advisory levels each day. Extreme Heat
  Warning along coastal SE GA and Heat Advisory in place other
  locations Friday.

High pressure situated over the Gulf of Mexico will shift northward
as an upper-level trough digs south along the Southeast coast
through Saturday. This transition will sufficiently weaken the
prevailing west-southwest flow to allow the Atlantic sea breeze to
penetrate farther inland, potentially reaching west of the I-95
corridor. Scattered showers and thunderstorms are expected to
develop each afternoon as the sea breeze interacts with the larger-
scale flow, with convective coverage reaching its peak near sea-
breeze and Gulf-breeze collisions.

For Friday, scattered to numerous afternoon and evening showers are
expected across much of the region. Winds will remain light out of
the southwest, veering south to southeast by the afternoon. High
instability and abundant moisture will support the potential for a
few strong storms capable of producing gusty winds and locally heavy
rainfall.

By Saturday, the approaching trough will drive a cold front
southward into the area, with the boundary projected to settle near
the Florida/Georgia state line by Saturday evening. This front will
serve as an additional focus for convection, with scattered to
numerous showers and storms  across Southeast Georgia and southward
toward the I-10 corridor during the afternoon with widely scattered
showers and storms elsewhere.  The current environment favors pulse
storms, with isolated strong wind gusts and locally heavy rainfall
possible.

Temperatures will remain elevated in the upper 90s to near 100
degrees through Saturday. Heat index values will frequently approach
Heat Advisory criteria, though afternoon convection may temper the
duration of peak heating. An Extreme Heat Warning will be hoisted
for coastal Southeast Georgia on Friday replacing the previous
watch, where heat index values could reach 112-114 degrees.

&&

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

- Warm temperatures continue over the weekend and next week, with
Heat Advisories likely

- Isolated to scattered thunderstorms each afternoon evening, which
could become strong

The cold front positioned near the Florida/Georgia border will lift
northward on Sunday before gradually clearing the area early next
week. This pattern will result in isolated to scattered showers and
thunderstorms on Sunday, with a subsequent decrease in coverage on
Monday. Another frontal boundary will approach from the north on
Tuesday and is expected to linger near the region through midweek,
leading to an increase in precipitation chances.

Persistent above-normal temperatures and dewpoints in the 70s will
maintain a prolonged stretch of hazardous heat through the period.
Afternoon heat index values will frequently range between 105-115
degrees, with Major to Extreme HeatRisk conditions possible across
portions of the forecast area. Overnight lows in the mid to upper
70s will offer minimal relief, and Heat Advisories will likely be
required periodically through next week. Tuesday currently appears
to be the warmest day of the forecast period.

Convective coverage should remain isolated to scattered each
afternoon and evening, with POPs around 20-40% Sunday, decreasing to
10-20% Monday, then increasing to 20-50% Tuesday through Wednesday
as the next frontal boundary approaches. While organized severe
weather is not expected, a few strong storms could produce gusty
winds and locally heavy rainfall, particularly near frontal
boundaries and sea-breeze collisions. The main forecast challenge
through the extended period will be the timing and coverage of daily
convection, which will also influence the intensity and duration of
the afternoon heat.

&&

.AVIATION /18Z THURSDAY THROUGH 18Z FRIDAY/...
West winds of 5-10 kts will prevail through the afternoon, with
winds at coastal sites becoming southerly between 19Z and 20z as the
Atlantic sea breeze pushes inland. Scattered showers and
thunderstorms are expected this afternoon into early evening, though
coverage should be lower than Wednesday. Will maintain PROB30 MVFR
TSRA from approximately 19-23Z, with subsequent updates to refine
timing and coverage. Thunderstorms will diminish after sunset, with
light winds and generally VFR conditions prevailing. The exception
will be VQQ, where visibility could briefly decrease to around 4SM
between 08-11Z.

&&

.MARINE...

A trough of low pressure will develop over the southeast states
through the weekend while a high pressure ridge remains
positioned over the eastern Gulf and central Florida. This will
result in westerly winds during the next several days, with the
sea breeze shifting winds to southeast or south over the near
shore waters each afternoon, followed by south evening wind
surges that may briefly increase speeds to near caution levels
before subsiding after midnight. Stronger offshore flow may
develop Monday and Tuesday next week. Isolated to scattered
mainly afternoon and evening thunderstorms will remain possible
each day through the upcoming weekend, and some of the storms
will be capable of producing strong gusty winds and locally high
seas.

Rip Currents: Prevailing offshore winds and little if any east-
southeast swell energy will keep surf heights near or below 2 feet
at area beaches. Thus, generally low risk of rip currents through
Friday. Only heightened risk of rip currents will be around piers
and jetties and also around the times of low tide, which for today
and Friday will be around 3 PM to 5 PM. Going into the weekend,
there is not much change with low surf heights so the low risk of
rips may continue.

&&

.FIRE WEATHER...
- Heat Headlines in Effect

Warm temperatures will continue through the end of the week, with
highs in the mid 90s inland and lower to mid 90s along the coast
today. Above-normal temperatures will persist through the weekend,
with additional Heat Advisories likely, although isolated to
scattered afternoon and evening thunderstorms may provide some
relief and limit the duration of heat index values near or above
advisory criteria. A cold front will move south into the area
Saturday and stall near the Florida/Georgia line Sunday, focusing
the highest storm chances along and south of the boundary,
particularly toward the I-10 corridor Saturday.

Fog Potential: Significant fog development is not expected. Any late-
night or early-morning fog should be shallow and patchy, mainly in
areas that receive locally heavy rainfall.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  96  76  97  76 /  20  10  40  20
SSI  96  80  95  80 /  10  10  40  20
JAX  96  76  96  77 /  30  10  50  10
SGJ  94  77  94  77 /  30  10  30  10
GNV  95  75  96  75 /  50  20  60  20
OCF  94  75  96  75 /  50  20  50  20

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory until 8 PM EDT this evening for FLZ021-023-024-
     030-031-035-038-120-124-125-132-136>138-140-220-225-232-
     233-236-237-240-322-325-333-340-422-425-433-522-533-633.
     Heat Advisory from 11 AM to 8 PM EDT Friday for FLZ021-023-024-
     030-031-035-038-120-124-125-132-136>138-140-220-225-232-
     233-236-237-240-322-325-333-340-422-425-433-522-533-633.
GA...Heat Advisory until 8 PM EDT this evening for GAZ132>136-149-
     151-152-162-163-250-264-350-364.
     Heat Advisory from 11 AM to 8 PM EDT Friday for GAZ132>136-149-
     151-152-162-163-250-264-350-364.
     Extreme Heat Warning until 8 PM EDT this evening for GAZ153-
     154-165-166.
     Extreme Heat Warning from 11 AM to 8 PM EDT Friday for GAZ153-
     154-165-166.
MARINE...None.

&&

$$