Jacksonville, Florida 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

305
FXUS62 KJAX 111728
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
128 PM EDT Fri Apr 11 2025

...New AVIATION...

.UPDATE...
Issued at 1018 AM EDT Fri Apr 11 2025

The inherited forecast hasn`t need many changes this
morning as a cold upper trough and attendant cold front push into
the area. The aforementioned front is nearing the Altamaha river as
of 10 AM and will push down into NE FL late this afternoon (4-6pm).
Dry air ahead will initially limit convective development. However,
as the front reaches a ribbon of moisture stretched along I-10
corridor and south, scattered showers and thunderstorms will begin
to initiate around 2-4 PM in that band of moisture.

It`s worth noting that GOES measured PWATs are generally less than
an inch, around 0.8-0.9". Despite lack-luster deep layer moisture,
sufficient instability, owing a cold pool aloft, will develop.
Sampled mid-level lapse rates around measured at 6.6 degC/km this
morning but should steepen toward the 90th percentile (7.2 degC/km)
this afternoon as air aloft cools. This instability may be
supportive of small hail development along with down burst winds
with stronger t`storms this afternoon. It follows that SPC has
contoured a Marginal (i.e. isolated) Risk of severe t`storms this
afternoon, mainly for areas of NE FL late this afternoon and
into the evening, roughly 4-9 PM.

&&

.SYNOPSIS...
Issued at 354 AM EDT Fri Apr 11 2025

Overnight surface analysis depicts weak low pressure (1014
millibars) developing over the southern Appalachians along a cold
front that extended southwestward from this feature across the
Deep South. Aloft...amplified troughing was digging south-
southeastward from the Great Lakes region, with a trio of potent
shortwave troughs spinning across the Upper Midwest, southern
Appalachians, and eastern Great Lakes. Otherwise, an outflow
boundary from widespread convection that developed across central
and northern GA earlier yesterday afternoon and evening has
reached coastal GA and SC, with this boundary developing a thin
line of convection along the Atlantic coast to the north of Sapelo
Island. Debris cloudiness from earlier convection was drifting
across the skies for locations along and north of Interstate 10,
with fair skies remaining in place over north central FL. Remnant
showers from overnight convection were skirting the Ocmulgee and
upper Altamaha Rivers. Temperatures at 08Z ranged from the lower
50s in the Suwannee Valley to the mid 60s at coastal locations.
Dewpoints ranged from the upper 40s over inland southeast GA to
around 60 at coastal locations.

&&

.NEAR TERM...
(through Tonight)
Issued at 354 AM EDT Fri Apr 11 2025

Deep troughing will continue to dig over the eastern third of the
nation through early Saturday. This trough will drive a strong
cold front across our region from northwest to southeast this
afternoon and evening. Temperatures aloft will cool substantially
this afternoon as the trough aloft digs into our area, and there
may be just enough moisture around to trigger scattered showers
and possibly a few strong to severe thunderstorms, especially for
locations along the Interstate 10 corridor. Bulk westerly shear
of around 60 knots and very cold temperatures aloft will create a
hail and downburst wind threat with any stronger storms that
develop. Activity will move quickly southeastward this evening,
likely exiting north central and coastal northeast FL towards
midnight.

A few showers that are leftover from overnight convection that
traversed northern and central GA will be possible through around
sunrise across inland southeast GA, mainly for locations north of
Waycross. Debris cloud cover will thin out early this morning,
allowing for plenty of insolation across our area, with
temperatures south of the advancing cold front climbing to the low
and mid 80s this afternoon for locations along and south of I-10.
The cold front will likely cross inland southeast GA during the
early and mid afternoon hours, where moisture will be scant and
rain chances will remain low. Developing cool air advection this
later this afternoon in the wake of the frontal passage will keep
highs in the mid to upper 70s for most of southeast GA.

Breezy west-southwesterly winds ahead of the front this afternoon
will bring 80 degree temperatures to the northeast FL beaches.
Short-term, high resolution guidance continues to pinpoint the
I-10 corridor for convective initiation in the 20Z-22Z time frame,
with activity then increasing in coverage as it moves quickly
east- southeastward. The Storm Prediction Center has maintained a
Marginal (level 1 out of 5) Risk for severe thunderstorm
development this afternoon for locations southeast of Waycross,
with hail and damaging wind gusts of 40-60 mph being the primary
threats. This risk may continue a little past sunset across
north central and coastal northeast FL as convection progresses
southeastward, with skies then clearing from northwest to
southeast overnight as convection exits our area. A northwesterly
breeze of 5-10 mph will drop lows to the upper 40s across inland
southeast GA and the Suwannee Valley, with lower 50s elsewhere
inland and mid to upper 50s for coastal locations.

&&

.SHORT TERM...
(Saturday through Sunday night)
Issued at 354 AM EDT Fri Apr 11 2025

High pressure gradually settles in throughout the day Saturday
post cold front, with a modest northwesterly flow throughout the
day winding down SAturday Night. A few diurnal clouds will be
expected during the afternoon and evening, with an otherwise
mostly sunny start to the weekend with highs a bit below normal,
generally in the low to mid 70s. Winds look to die down enough
Saturday Night for some good radiational cooling conditions inland
under mostly clear skies. Lows in the mid to upper 40s will be
common inland, with low to mid 50s by the coast and St. Johns
River.

Benign conditions continue into Sunday as high pressure continues
to sink towards the area, positioned directly over the Florida
Peninsula Sunday Evening and Sunday Night. Mainly sunny skies
continue with the low level subsidence, with temps rebounding a
couple degrees to the mid to upper 70s. A rather weak sea breeze
is expected to develop and slowly move inland Sunday afternoon and
evening with the very weak synoptic flow, which will cap high
temps in the low to mid 70s closer to the coast.

&&

.LONG TERM...
(Monday through Thursday)
Issued at 354 AM EDT Fri Apr 11 2025

High pressure starts to move eastward into the Atlantic on Monday
as our next front starts to approach from the northwest Monday
Night and Tuesday. Moisture looks rather limited with this front,
though depending on the exact timing, some convection looks to be
possible sometime between Tuesday afternoon and Wednesday Morning.
High pressure builds into the region once again behind the front
Wednesday and into Thursday. Return flow Monday and Tuesday will
result in temperatures above average during this time frame,
falling closer to average once again for Wednesday and Thursday.

&&

.AVIATION...(18Z TAFS)
Issued at 128 PM EDT Fri Apr 11 2025

A shallow cumulus field has begun to develop along a cold front
extending from KTLH to KSSI. That boundary will move into a
destabilizing air as it moves into NE FL and this should initiate
storm development around 20-21z. Isolated storms may become strong
and produce wind gusts up to 35 knots and potentially small hail.
Convection will peak in intensity between 22z and 01z, with
potential impacts at airfield along the I-10 corridor, with
weakening trends thereafter. Brief MVFR ceilings may accompany rain
and storms as they pass. Outside of showers and storms, VFR
conditions prevail. Winds will favor a westerly direction with gusts
up to 20-25 kts ahead of the front then switch to northwesterly
behind the front.

&&

.MARINE...
Issued at 354 AM EDT Fri Apr 11 2025

West-southwesterly winds will gradually strengthen today ahead of
an approaching cold front that will cross our local waters this
evening. Scattered showers and thunderstorms will develop late
this afternoon and early this evening along this cold front, with
a few strong or possibly severe storms possible. Stronger storms
will be capable of producing strong wind gusts, hail, and frequent
lightning strikes. Seas of 3-5 feet will prevail both near shore
and offshore through Saturday afternoon. Winds will shift to
northwesterly later tonight in the wake of this frontal passage,
with high pressure then building over our local waters during the
weekend, allowing winds and seas to subside beginning on Saturday
evening. High pressure will then shift east of the Florida
peninsula on Monday as a cold front enters the southeastern
states. West-southwesterly winds will gradually increase ahead of
this approaching front on Monday night and Tuesday, with this
front forecast to cross our local waters on Tuesday afternoon or
evening. Seas of 2-4 feet will prevail throughout our local waters
from Saturday night through early next week.

Rip Currents: A persistent east-northeasterly ocean swell and
elevated breaker heights of 3-5 feet at the northeast FL beaches
and 2-4 feet at the southeast GA beaches will yield a higher end
moderate risk at all area beaches today. The lingering swell will
likely result in a lower end moderate risk at the northeast FL
beaches on Saturday, with a low risk expected at the southeast GA
beaches, where surf heights will fall to 2 feet or less. A low
risk is then expected from Sunday through Tuesday as surf heights
remain at 2 feet or less.

&&

.FIRE WEATHER...
Issued at 354 AM EDT Fri Apr 11 2025

High daytime dispersions are expected area-wide this afternoon and
evening, as well as during the afternoon and evening Saturday. Min
RH values in the upper 20s to low 30s of percent will also be
expected each afternoon and evening with excellent mixing. There
is a marginal risk of an isolated strong to severe thunderstorm
today as a cold front moves through the region, with erratic gusts
of 40-60 mph and small hail the main threats. Most activity is
expected to be confined to northeast FL.

&&

.HYDROLOGY...
Issued at 354 AM EDT Fri Apr 11 2025

Upstream runoff has created routed flow down the Ocmulgee and
Oconee Rivers that will result in rises along upper portions of
the Altamaha River this weekend and early next week. Water levels
are forecast to rise above flood stage near the gauge at Baxley
on Monday, with water levels cresting just below flood stage by
Tuesday near the gauge at Charlotteville.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  75  48  71  44 /  20   0   0   0
SSI  80  54  72  53 /  20  20   0   0
JAX  82  52  75  48 /  50  50   0   0
SGJ  83  55  73  53 /  30  50   0   0
GNV  82  51  75  47 /  30  60   0   0
OCF  82  51  75  47 /  10  40   0   0

&&

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

$$