915
FXUS62 KJAX 210641
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
241 AM EDT Fri Aug 21 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

- Heat Advisories for NE FL and portions of SE GA today

- Isolated strong to severe thunderstorms today and Saturday for
  portions of the area, mainly across southeast GA.

- Limited thunderstorms Sunday and Monday, followed by daily
  scattered thunderstorms Tuesday onward.

&&

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

- Heat advisories in effect for portions of the area Today

- Potential for strong to severe thunderstorms this afternoon
  and evening


Weak surface troughing will extend south across the area Friday,
from a low over the Carolinas. An upper trough will move east toward
the region this period.

The combination of diurnal heating, sea breeze interactions, and a
gradual increase in instability from upper trough, will yield the
production of showers and thunderstorms Friday, mainly during the
afternoon and evening hours. With the upper trough moving in Friday
night, this activity could linger into the overnight.

As has been the case the last few days, storms which develop could
become strong with isolated severe storms possible.

Above average temperatures are expected Today, with near average
Tonight. Drier air will linger over inland SE GA, limiting the need
for Heat Advisories there. For the rest of the area, convection may
limit heat, but potential is still high enough for an advisory.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...

Main Highlights This Period:

- Strong to possibly isolated severe thunderstorms possible Saturday.

- Heat Advisory level conditions possible for NE FL on Sunday.

Moist, southwesterly flow remains in control through Saturday and
intensifies as an upstream upper trough buckles and digs equatorward
toward the region through the day Saturday. The upper wave will be
accompanied by a surface front and prefrontal trough which will
serve as the primary focus of convective initiation Saturday
afternoon as the pinned Atlantic sea breeze focuses scattered
convection along it during the late afternoon. At this time, the
prefrontal trough is progged to sag across south of the Altamaha and
possibly US-82 by the afternoon hours on Saturday, training and
strong convective development is likely along this boundary. Cooler
air aloft will support steeper mid level lapse rates and the
potential for isolated pulse severe storms through the early evening
hours Saturday for most of NE FL and SE GA. Main concerns will be
localized flooding and wind damage related to downburst activity.
Temperatures will be closer to typical heat levels for late August
with highs in the low 90s and peak heat index in the 100-105 degree
range.

By Sunday, the northwesterly flow will push the slowing frontal
feature into SE GA where it`ll stall. The drier airmass will allow
dewpoints to mix out through the afternoon with temperatures soaring
into the upper 90s amid the drier airmass under mostly sunny skies.
Further south across NE FL, sufficient moisture will be in place to
facilitate the development of isolated to scattered thunderstorms
south of I-10. A few stronger storms may develop along I-95 corridor
and  the pinned Atlantic sea breeze during the late afternoon and
early evening. While highs will be in lower 90s in NE FL, the higher
mid 70s dew points may allow peak heat index to be near Heat
Advisory levels prior to the onset of convection.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...

Main Highlights This Period:

- Hot and dry Monday followed by increasing Thunderstorm chances
  Tuesday onward.

The broader pattern will keep an initially drying northwesterly flow
established across the region, limit rain chances through at least
Monday before deeper moisture returns by Tuesday. Expansive upper
ridging centered across the southwestern US will consolidate through
the middle of next week, which will "open the door" to peripheral
shortwaves moving along the ridge and direct them right into the
local area. Current medium range guidance has this scenario playing
out Tuesday and again Thursday which should bring added forcing for
ascent and result in increasing coverage in afternoon convection
amid the persistent southwesterly steering flow. The hottest day will
be Monday as a dry airmass heats up in to the mid/upper 90s. Above
normal temperatures are expected to continue through the week with
highs generally in the low 90s Tuesday onward.

&&

.AVIATION /06Z FRIDAY THROUGH 06Z SATURDAY/...

VFR conditions will prevail early this period, but a little patchy
fog will be possible inland.

Convection will get an earlier than usual start Today, with activity
beginning during the morning inland, then spreading northeast
through the afternoon and evening. Convection may linger into the
night Tonight. Gusty and erratic winds will be possible in and near
storms.

&&

.MARINE...

A frontal zone will extend across the Carolinas and into Georgia
this period, with a high pressure ridge to the southeast. Rounds of
mainly afternoon and evening showers and thunderstorms can be
expected each day.

Rip Currents: Offshore winds will prevail throughout the morning
hours, along with low surf heights, during the next several days.
With the outgoing tide occurring later in the afternoon, the overall
risk will be low today and low to low end moderate this weekend as
an afternoon seabreeze brings light south to southeast winds to the
beaches.

&&

.FIRE WEATHER...

Scattered thunderstorms are expected to develop across inland
portions of southeast GA and along the sea breezes this afternoon
and early evening. Additional rounds of thunderstorms are expected
Saturday before drier air limits chances on Sunday and Monday.
Outside of thunderstorm outflow winds, light southwesterly wind will
be favored for inland areas not influenced by the east-coast sea
breeze. The incoming drier air will lead to hot and dry conditions
north of I-10 with afternoon humidity down in the 30-40% range
Sunday and Monday afternoon. Thunderstorms chances start to ramp
back up on Tuesday.

Fog Potential: Considerable fog is unlikely, and any strong wind
will be associated with nearby thunderstorm activity.

&&

.CLIMATE...
Less likely to push to record territory today but chances
increase in near record heat by Sunday as drier airmass enters
the region.

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

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  97  72  93  73 /  60  70  50  10
SSI  93  77  92  77 /  30  30  60  20
JAX  94  73  92  73 /  50  30  60  20
SGJ  94  75  92  75 /  40  20  50  10
GNV  93  73  90  73 /  40  20  70  20
OCF  93  74  90  74 /  30  20  60  20

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory from 11 AM this morning to 7 PM EDT this evening
     for FLZ021-023-024-030-031-035-038-120-124-125-132-
     136>138-220-225-232-233-236-237-322-325-333-422-425-433-
     522-533-633.
GA...Heat Advisory from 11 AM this morning to 7 PM EDT this evening
     for GAZ136-152>154-162-163-165-166-264-350-364.
MARINE...None.

&&

$$