450
FXUS62 KJAX 131409
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
1009 AM EDT Sun Sep 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

- Moderate Rip Current Risk all Local Beaches Today and Friday.
Elevated Risk Returns Early Next Week

- Daily Heat Index up to 107 through Sunday

- Daily Afternoon & Evening Thunderstorms. Main Hazards: Locally
Heavy Rain, Lightning & Gusty Winds Up to 40-50 mph

&&

.UPDATE...

In the midst of pooled moisture ahead of trough has provided a near-
saturated upper air observation the morning, with measured
precipitable water at 2.36" again which is not to far of from the
statistical max for mid September (PWAT 2.38"). While there has been
some slight cooling the in upper levels, which could support more
frequent or excessive lightning, warming in the mid levels has also
occurred, leading to weaker lapse rates and potential energy for
thunderstorms later on today, mainly during the early afternoon.

The big picture remains the same, with dry northwesterly flow,
associated with a shearing/dampening shortwave, making it into
interior SE GA by this afternoon limiting thunderstorm activity
while elsewhere there is a 30-60% chance of thunderstorms this
afternoon and early evening. The primary focus for convection will
once again be along the I-95 corridor with a near west-to-east
steering flow in place acting the slow the Atlantic sea breeze and
St Johns River breeze from advancing inland/westward.

As has been the situation regarding thunderstorm hazards over the
last few days, frequent lightning, gusty outflow winds, and
localized flooding are the primary concerns. Timing with CAMs has
been relatively solid, indicating expanding shower development
through 2 PM followed by scattered thunderstorm potential increasing
thereafter as mesoscale boundaries and outflows interact.

Rain and thunderstorms will bring some relief in terms of
temperature, but expect heat index to move quickly into the 100s by
noon today as temperature rises into the low 90s. Drink plenty of
water and seek shade during outdoor activities today and, as always,
when thunder roars, head indoors.

&&

.AVIATION /12Z SUNDAY THROUGH 12Z MONDAY/...
VFR conditions will continue through 13z with brief periods of
broken MVFR ceilings at inland terminals (KJAX/KGNV/KVQQ) as low
level moisture lifts. Surface winds will be light westerly with a
sea breeze developing by 18z-20z for SSI, SGJ, and CRG switching
winds to the southeast. Westerly steering winds aloft will push
isolated to scattered showers and thunderstorms toward the I-95
corridor where stronger storms may develop due to sea breeze and
outflow collisions. Localized IFR to LIFR conditions are possible
due to heavy rain limiting visibility. Convective activity will fade
after sunset with drier air limiting stratus and fog potential
tonight for sites along and north of I-10 Monday morning.

&&

.MARINE...


Offshore winds will continue across the area waters today and on
Monday, except for a sea breeze which will shift winds to the
southeast and south during the afternoon hours. Another good chance
of a couple of strong thunderstorms this afternoon and evening.
Strong gusty winds and very heavy rainfall will accompany the
stronger storms. On Monday, less thunderstorm activity is expected
and likely be limited to northeast Florida nearshore waters. From
Tuesday through Thursday, a strong northeast wind surge will bring
small craft advisory conditions, rough seas, and numerous showers
and a few thunderstorms over the area waters.

Rip Currents: Prevailing offshore winds (except for an afternoon
sea breeze) and weak easterly swells will keep a low-end moderate
risk of rip currents in effect the next couple of days. By Tuesday,
strengthening northeast winds and building surf are expected which
will continue into Thursday. This should result in a high rip
current risk and dangerous surf at all area beaches during this time
period.

&&

.FIRE WEATHER...
     PATCHY TO AREAS OF HIGH DISPERSIONS TUESDAY THROUGH THURSDAY
- Afternoons

A trough of low pressure will stretch across the southeastern US
this weekend. High pressure will build to the northeast early next
week, and strengthen through mid week. As this high builds, an
inverted trough will develop east of the area. The gradient between
these two features will result in elevated winds Tuesday through
Thursday, especially at the coast. An inverted trough will settle
overhead late in the week into the weekend. Daily thunderstorm
chances are forecast, mainly in the afternoon and evening hours.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  92  73  94  73 /  10  10   0   0
SSI  91  77  92  79 /  20  20   0   0
JAX  92  75  93  75 /  40  20  10   0
SGJ  91  76  91  76 /  40  30  10  10
GNV  92  74  93  74 /  40  20  40  10
OCF  92  75  93  74 /  50  20  50  20

&&

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

&&

$$