603
FXUS62 KJAX 052325
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
725 PM EDT Tue Aug 5 2025

...New UPDATE, AVIATION...

.UPDATE...
Issued at 725 PM EDT Tue Aug 5 2025

For the latest NE FL and SE GA Daily Key Messages please visit:
https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf

Most of southeast Georgia and northeast Florida are clear of
storms this evening, expect for the I-95 corridor eastward,
south of Jacksonville. Some showers will linger after sunset, but
storm chances will decrease significantly. Tonight, mild lows
expected in the lower to mid 70s.

&&

.NEAR TERM...
Issued at 145 PM EDT Tue Aug 5 2025

For the latest NE FL and SE GA Daily Key Messages please visit:
https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf

Current analysis is hinting towards decent downburst potential
this afternoon and evening with any strong storm development near
the I-95 corridor and across southeast Georgia. PWATs are sitting
near 2.0" with DCAPE generally at 800-1000, as storms move
northeastward and reach the Atlantic sea breeze, expect collisions
to enhance strong storm potential. Steering flow is a bit stronger
than the past few days, but still slow enough that slow moving
strong storms may cause flooding concerns, especially in locations
that received a lot of rain the last few days as well as in urban
areas. Convection will begin to weaken around sunset, with some
storms lingering a few hours later.

&&

.SHORT TERM...
(Wednesday through Thursday night)
Issued at 145 PM EDT Tue Aug 5 2025

Synopsis...Localized flooding rainfall risk continues each day
with a surface front draped across the local area interacting with
daily sea breezes from both the Gulf and Atlantic. There is also
an increased chance of more strong to pulse severe storms with a
mid/upper level trough axis nosing eastward from the FL panhandle.

Wednesday, a weaker WSW steering flow < 5 kts will enable both sea
breezes to progress inland into the afternoon, with the highest
rain chances focused between the I-75 corridor and Highway 301
during the late afternoon and early evening. There is an area of
lower precipitable water (PWAT) noted offshore of the SW FL
Atlantic coast today, and given the steering flow this `drier` air
will rotate northward and across NE FL into Wednesday morning and
limit Gulf coast convection in the morning compared to previous
days. The higher moisture Wednesday will focus across southeast GA
and north of the FL Interstate 10 corridor in the afternoon and
evening where PWAT rises to near 2.4 inches as a short  wave
trough passes overhead. The passage of the mid level trough will
bring steeper mid level lapse rates and some enhanced bulk shear,
which in addition to the heavy rainfall threat, will also increase
pulse severe storm threat mainly across SE GA and toward the
Golden Isles into Wed evening where stronger storms will be
capable of damaging wet downbursts winds nearing 60 mph.
Convection presses offshore Wed evening and weakens, with mostly
dry conditions after midnight.

Thursday, surface high pressure strengthens northeast of the
region, with breezier NE winds at the coast and a stronger east
coast sea breeze. Deeper PWAT over 2 inches will filter across the
entire forecast area, bringing more widespread convection and a
focus for boundary collisions west of the Highway 301 corridor and
toward I-75 into the late afternoon and into the evening. The
mid/upper level trough axis will slide closer to the local area
into Thursday, with cooler temperatures aloft and passing PVA from
the WSW again enhancing strong to pulse severe storm potential.
Convection across inland areas will gradually decrease in
intensity overnight Thu night, but onshore easterly flow and a
developing coastal trough will bring coastal showers and isolated
storms onshore into Friday morning.

&&

.LONG TERM...
(Friday through next Tuesday)
Issued at 145 PM EDT Tue Aug 5 2025

Fri-Sun...Onshore, easterly flow will bring waves of showers and
storm to coastal areas as an inverted coastal trough approaches
the southeast Atlantic coast. The National Hurricane Center
continues to monitor this trough axis as a catalyst for potential
tropical cyclone development with a 40% chance of low pressure
forming along this boundary over the next 5-7 days as it nears the
Atlantic seaboard. Most forecast ensembles continue to have a
broad surface low or open trough axis. Regardless of tropical
cyclone development, this feature will bring an elevated coastal
flash flood risk Friday into the weekend as training bands of
rainfall come onshore over 1-3 days. Morning convection will
expand inland each day toward the I-75 corridor into the afternoon
and early evening. In addition, the persistent easterly and
elevated easterly swells will bring an elevated rip current risk.
Looking at recent water levels, the St. Johns River basin could
near Action to low end Minor Flood Stage into the weekend due to
persistent early flow. Temperatures will trend near to below
normal for highs given storminess and near to above normal for
lows with onshore easterly flow.

Mon-Tue...Prevailing easterly steering flow continues with a dominant
east coast sea breeze convective regime. The main story will be
increasing temperatures early next week as a stronger 596 dkm 500
mb ridge builds over the southeast region. Heat index values climb
back into the 105 to potentially 110 deg range, flirting near
Heat Advisory levels.

&&

.AVIATION...
(00Z TAFS)
Issued at 725 PM EDT Tue Aug 5 2025

Most sites are clear of thunderstorms for the evening, with some
lingering light rain at SSI, and storms moving eastward towards
SGJ through 01Z. Tonight, there is a chance of some lower
visibilities at GNV and VQQ, although confidence at GNV is not
high at this time, so just have 6SM BR in there. Diurnal storms
will impact the sites beginning around 18Z Wednesday, with PROB30s
in place for timing of highest storm chances.

&&

.MARINE...
Issued at 145 PM EDT Tue Aug 5 2025

A stalled front will extend across the Georgia waters today will
gradually shift southward late tonight into Wednesday as high
pressure wedges down the east coast from the north and a coastal
trough forms well off of the Florida coast by late this week. This
pattern will bring shift prevailing south to southwest flow towards
more onshore mid to late week. The National Hurricane Center is
monitoring an area of potential tropical cyclone off the Southeast
coast later this week that may organize and shift westward towards
the coast this weekend. Continue to monitor NHC forecasts through
the week.

Rip Currents: Moderate Rip Current risk maintained through
midweek as seabreeze today and onshore flow Wednesday will bring
wave heights of 2-4 ft.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  72  90  72  87 /  50  70  60  70
SSI  77  90  76  87 /  60  60  70  80
JAX  74  93  75  90 /  50  60  50  80
SGJ  75  91  77  90 /  40  60  40  80
GNV  74  95  74  93 /  40  70  30  80
OCF  74  94  75  93 /  30  70  30  80

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&

$$