012
FXUS62 KJAX 190008
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
808 PM EDT Tue Aug 18 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

- Dangerously HOT Weather Continues this Week. Extreme Heat Warning
and Heat Advisories Today from 11 AM  8 PM. Heat Advisory for most of
the area Wednesday. Heat Advisories possible again Thursday through
Friday

- Scattered to Numerous TStorms Each Afternoon & Evening through.
Main Impact Areas through Thursday: Northeast and North Central FL.
Strong Storms are Possible Each Day, Mainly Along the I-95 Corridor.
Primary Hazards: Wind Gusts of 40-55 mph, Frequent Lightning Strikes,
and

&&

.UPDATE...
Severe thunderstorms have subsided for the evening with showers
and storms situated south of the I-10 corridor expected to move
southward and dissipate from out of the forecast area overnight,
with calm weather in place going into Wednesday morning.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Main Highlights through Tonight:

- Dangerous Heat Index & Near Record High Temperatures - Extreme
Heat Warnings and Heat Advisories through 8 pm today.

- Strong Thunderstorms Late Afternoon and Evening Northeast FL

Latest early afternoon heat index values were approaching 108-110
inland to 110-115 deg at the coast. Extreme Heat Warning continues
for all of northeast FL, Echols county and coastal southeast GA
through 8 pm with a Heat Advisory for the remainder of inland
southeast GA.

Dominant surface trough continues draped across north GA with mean
layer high pressure extending from across the central Gulf of
America to across the across the Bahamas. A few low level surface
troughs extended south of the parent trough, one sliding south of
Marion county with convection into north central FL. Convection is
still expected to resurrect later this afternoon and into the early
evening with the main focus area across northeast Florida where
deeper moisture (PWATs > 2 inches) combine with mesoscale boundaries
including the sea breezes and weak troughs. Drier air mixing down
across southeast GA generally north of Waycross to Jesup will limit
convective coverage into the evening with rain chances < 20% while
the higher rain chances of near 60% were advertised between I-95 and
the Highway 301 corridor of northeast Fl between 5 pm and 8 pm this
evening. The main hazards in resultant storms will be localized
heavy rainfall and wet downbursts in storm mergers.

Convection will tapper off inland into the evening with lingering
stratiform through about midnight across the Suwannee River Valley.
Muggy overnight conditions continue with lows in the mid to upper
70s.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
Main Highlights This Period (Wednesday and Thursday):

- Greatest chance for thunderstorms this period over NE FL during
the afternoon and evening hours, with a few strong storms possible

- Heat Advisories in effect for Wednesday, another likely needed on
Thursday

Predominately northwest/west steering flow Wednesday will bring in
drier air across southeast Georgia, and allow the Gulf sea breeze to
push far inland and meet the Atlantic sea breeze closer to the east
coast. Overall, precipitation chances will be <30% across southeast
Georgia, and highest storm chances will be east of Gainesville
towards the northeast Florida beaches. Hazardous heat continues on
Wednesday, with high temperatures in the mid to upper 90s,
potentially near 100 for some inland southeast Georgia locations.
Maximum afternoon heat index values will be around 106-113 degrees
for northeast Florida and the Georgia coast, drier air over inland
southeast Georgia will keep afternoon heat indices near 100-103
despite highs in the upper 90s. Best chances for reaching 100
degrees will be along the Altamaha River Basin.

Thursday, steering flow shifts more southerly/southwesterly,
allowing the Atlantic and Gulf sea breezes to meet in a more central
location, increasing storm chances between I-75 and I-95. Some
moisture will recover over inland southeast Georgia, bringing
scattered rain and storm chances. Once again, high temperatures will
be in the mid to upper 90s and near 100 across inland southeast
Georgia. Another Heat Advisory will likely be needed for at least
the southeast Georgia coast and portions of northeast Florida.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Main Highlights This Period (Friday through Monday):

- Near Record Heat and Dangerously High Heat Indices Continue on
Friday

- Scattered to Numerous Afternoon and Evening Thunderstorms Each Day
from Friday through the Upcoming Weekend

A front will be lingering across Georgia through this period,
enhancing moisture across the area Friday and Saturday as
southwesterly flow continues. Scattered to numerous showers and
storms are expected Friday and Saturday, with the southwest winds
promoting strong storm potential closer to the east coast where the
two sea breezes will interact. By Sunday, drier air moves in again
over southeast Georgia, lowering precipitation chances Sunday
onward. Highs in the mid to upper 90s continue Friday, `cooling`
slightly this weekend into the lower to upper 90s. Most of the area
will again approach Heat Advisory criteria on Friday with max
afternoon heat index values possibly finally remaining below
Advisory criteria this weekend.

&&

.AVIATION /00Z WEDNESDAY THROUGH 00Z THURSDAY/...

Showers and storms in the vicinity of GNV will continue to develop
southward through this evening with convection clearing from GNV
before 02z. Conditions will be predominantly VFR through into
Wednesday with mild overnight southwesterly sustained winds building
to about 8 to 10 knots in the afternoon with convective developments
expected to form for northeast Florida sites by around 20z to 22z.

&&

.MARINE...

A surface front will continue to linger across the southeast region
with Atlantic coast high pressure extending across the Bahamas. This
pattern will continue a prevailing southwest to south wind pattern
across the local waters with brief surges near Small Craft Exercise
Caution wind criteria in the afternoons and evenings. A daily east
coast sea breeze will bring winds south to southeast along the
immediate coast. Daily showers and isolated storms will impact
mainly the coastal waters east of Florida.

Rip Currents: Prevailing offshore winds and low surf heights will
keep a low risk in place through at least midweek at area beaches.
Offshore winds will decrease slightly by Thursday and Friday,
allowing the afternoon sea breeze to create breezy onshore winds
that may result in a lower end moderate risk at the northeast FL
beaches on Thursday and Friday.

&&

.FIRE WEATHER...
     HEAT ADVISORIES AND EXTREME HEAT WARNINGS IN EFFECT TODAY AND
- Wednesday

- Patchy High Daytime Dispersions Southeast Georgia Wednesday

The region will be between high pressure to the south, and a frontal
zone to the north this period. Thunderstorms will be in the forecast
each afternoon and evening this period. Overall, drier air will be
in place over inland southeast Georgia, but above critical minimum
relative humidity values. Patchy high dispersion is forecast for
Wednesday afternoon across southeast Georgia, and will be fair to
good for the rest of the week. It will be an abnormally hot week,
with readings returning to more seasonal levels over the weekend.

Fog Potential: Significant fog formation is not expected. Gusty and
erratic winds are possible within stronger thunderstorms.

&&

.CLIMATE...
Near record high temperatures are possible at some of our designated
climate sites during the next several days:

Tuesday, August 18:
KJAX: 98/1954
KGNV: 98/1954
KAMG: 105/1995
KCRG: 96/2023

Wednesday, August 19th:
KJAX: 99/1900
KGNV: 100/1954
KAMG: 103/1995
KCRG: 97/2010

Thursday, August 20th:
KJAX: 101/1900
KGNV: 99/1900
KAMG: 104/1995
KCRG: 98/2016

Friday, August 21st:
KJAX: 101/1900
KGNV: 99/1983
KAMG: 100/1980
KCRG: 99/2016

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  77  98  74  98 /  20  20  10  30
SSI  80  97  79  95 /  20  10  30  20
JAX  78  97  75  95 /  40  40  30  50
SGJ  78  95  77  93 /  30  30  20  50
GNV  77  94  75  94 /  40  60  30  70
OCF  78  94  76  94 /  40  60  20  80

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory from 11 AM to 8 PM EDT Wednesday 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 from 11 AM to 8 PM EDT Wednesday for GAZ153-154-
     162-163-165-166-264-350-364.
MARINE...None.

&&

$$