360
FXUS62 KJAX 201902
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
302 PM EDT Thu Jun 20 2024

...POTENTIAL FOR LOCALLY HEAVY RAINFALL AMOUNTS TONIGHT INTO
FRIDAY FOR PORTIONS OF NORTHEAST FLORIDA...

.NEAR TERM...
Issued at 237 PM EDT Thu Jun 20 2024

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

Isolated showers will continue to push onshore at times through
the rest of this afternoon with heavier showers approaching the
coast late this afternoon towards sunset off the Flagler and
St Johns county coast as a weak low approaches our area from the
western Atlantic waters north of the Bahamas. Easterly to east
northeasterly winds will stay in the 15-25 mph range from I-95 to
the beaches to more 10-15 mph farther inland with higher gusts
along the coast to 25-30 mph. temperatures will stay in the mid
80s along the coast with upper 80s to around 90 degrees along and
west of I-75 in NE FL and US441 in SE GA.

Tonight, a weak low will move west to west northwest towards
the NE FL coast south of St Augustine with rounds of numerous to
widespread showers and embedded thunderstorms spreading north
along the coast to I-95 and then pressing inland towards the St
Johns river and to US highway 301 by dawn. Could see locally heavy
rainfall amounts of 2-3 inches along the NE FL coast to the St
Johns river, but most likely amounts will be around 1 to 1.5
inches over St Johns and Flagler counties, in the half inch to
an inch range for most locations east of highway 301 with less
amounts over inland SE GA. A few heavier showers may also bring
wind gusts up to 35-40 mph, but winds will mostly be breezy at
the immediate coast overnight in the 15-20 mph range gusting to
30 mph and 10-15 mph inland. These elevated onshore winds at the
coast will keep lows in the upper 70s at the coast, mid 70s along
I-95, lows 70s inland with some upper 60s northwest of Waycross.

&&

.SHORT TERM...
(Friday through Saturday night)
Issued at 237 PM EDT Thu Jun 20 2024

Area of low pressure with disorganized convection will move west-
northwest toward SE GA and NE FL during the overnight hours and
then move inland around or just after sunrise Friday morning.
There is no much time for the system to get organized, but there
is a small chance it can be a depression before it comes ashore.
Either way, impacts are the same with rough surf, potential minor
beach erosion during high tide, high risk of rip currents. Expecting
numerous showers with embedded thunderstorms with this feature,
along with elevated winds and gusts particularly I-95 eastward
where some wind gusts exceeding 30 mph are possible. Highs Friday
will be a little cooler than normal due the clouds and rainfall
passing through with highs in the 85 to 90 degree range.

High pressure will build to the northeast behind the low pressure
area Friday night through Saturday. This pattern will continue
the onshore flow pattern, but the gradient will be more relaxed,
so so not expecting winds to be as elevated during this time frame.
Above average shower chances will continue in the onshore flow.
Diurnal heating could lead to a few afternoon storms on Saturday.
Lows Friday night will generally be in the lower to mid 70s,
except a little warmer near the coast. Temperatures Saturday will
trend above normal, with highs ranging from the lower 90s at the
coast, to the mid 90s inland.

The high will move further away to the east northeast Saturday
night, with the flow becoming more from the south/southeast. Lows
away from the coast in the mid 70s, upper 70s coast.

&&

.LONG TERM...
(Sunday through next Thursday)
Issued at 237 PM EDT Thu Jun 20 2024

The high will continue to drift away to the east this period, as a
trough moves into the southeastern US and stalls. An increasingly
moist southwest flow will become the trend this period. This pattern
will produce above normal chances for showers and thunderstorms.
Temperatures will be above normal throughout this period.

&&

.AVIATION...
(18Z TAFS)
Issued at 237 PM EDT Thu Jun 20 2024

Gusty easterly winds continue through 00Z with gusts ranging in
the 15-25 kt range. Isolated showers continue to move onshore this
afternoon occasionally forming into convergent bands. Winds become
more NE tonight after sunset with more widespread MVFR CIGS.
Numerous light rain showers and isolated t-storms develop for the
coastal TAFs after 06z during the predawn hours as an area of low
pressure moves toward the FL coast. Showers and isolated storms
spread further inland after 10Z.

&&

.MARINE...
Issued at 237 PM EDT Thu Jun 20 2024

Strong high pressure will sink southward over the western Atlantic
waters east of the Mid Atlantic coast through tonight with small
craft advisory conditions continuing over the local waters. Weak
troughing over the area waters will help to bring occasional light
showers across the waters through early this evening. Tonight, a
weak low currently northeast of the Bahamas will move westward as
the high to the northeast shifts more eastward into the western
Atlantic. The weak low will move onshore early Friday morning and
then exit to the west through the day towards the northeast Gulf
of Mexico. The pressure gradient between the high to the northeast
and the low moving through the region will continue small craft
advisory conditions through much of Friday before the pressure
gradient relaxes due to the low departing and the high weakening.
Seabreeze circulations will create increasing coverage of showers
and thunderstorms along the coast and local waters this weekend
as light southeast flow prevails. A cold front will approach early
next week with winds becoming more southerly and elevated chances
for showers and thunderstorms.

Rip Currents: High risk of rip currents in effect for northeast FL
and southeast GA beaches due to strong onshore flow through Friday.
High surf advisory also in effect for northeast florida beaches
as surf/breakers remain 5-7 ft and range 4-6 ft along the
southeast GA beaches. With the approach of the full moon later
this week, water levels will start to run above normal but coastal
flooding is not expected at this time in the onshore flow.|

&&

.FIRE WEATHER...
Issued at 237 PM EDT Thu Jun 20 2024

A wave of low pressure will move west and affect the area late
tonight through Friday morning with numerous showers and scattered
thunderstorms for much of the area. High pressure will build
further away to the east northeast Friday night through Saturday.
The high will drift further away to the east later in the weekend
into next week, as a trough of low pressure slides into the
southeastern US and stalls. This will allow a moist southwesterly
to persists next week allowing scattered to numerous shower and
thunderstorm activity.

&&

.HYDROLOGY...
Issued at 237 PM EDT Thu Jun 20 2024

The Weather Prediction Center has a Marginal risk of excessive
rainfall for tonight where locally heavy rainfall amounts of 2 to
3 inches are possible across coastal NE FL as a weak low moves
from north of the Bahamas west northwest into the southern portion
of the the NE FL coast near or south of St Augustine with rounds
of heavy showers and embedded thunderstorms moving onshore from
the Atlantic waters. Urban locations within the I-95 corridor may
experience minor flooding in poor drainage and low lying areas.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  69  90  73  92 /  40  60  30  80
SSI  77  87  77  88 /  60  80  60  70
JAX  75  88  74  92 /  70  80  50  80
SGJ  77  87  75  90 /  80  80  60  80
GNV  73  89  72  93 /  60  80  30  90
OCF  74  91  75  95 /  50  70  30  90

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through late Friday night for FLZ124-125-
     133-138.

     High Surf Advisory until 5 PM EDT Friday for FLZ124-125-133-138.

GA...High Rip Current Risk through late Friday night for GAZ154-166.

AM...Small Craft Advisory until 5 PM EDT Friday for AMZ450-452-454-
     470-472-474.

&&

$$