571
FXUS62 KJAX 211130
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
730 AM EDT Sat Sep 21 2024

...New AVIATION...

.NEAR TERM...(through Tonight)

Patchy light fog has started to develop inland and will likely build
into a few areas of fog from the Suwannee Valley northward into
inland SE GA over the next few hours. Locally dense, transient fog
may develop in those areas as well, with visibility dropping to
1/2 mile or less.

High pressure wedging in from the north will compress gradients,
bringing a "mini" surge of northeasterly winds today. A subtle,
inverted trough offshore has enhanced shower activity mainly
across the adjacent Atlantic waters. The northeasterly low level
flow will push waves of low-topped showers into the coastal areas
from St Augustine south through the day. Due to the dry air
aloft, thunderstorm development is unlikely. However, a few
showers rolling onshore may offer breezy gusts up to 35 mph.
Outside of any showers winds will be breezy along the coast,
gusting up to 25 mph. Breeziness will begin to relax this evening
as the gradients begin to decompress with a gradual weakening of
the surface ridge. Temperature trends today will follow very close
to yesterday with highs pushing into the mid/upper 80s except at
the coast where low/mid 80s are expected.

Tonight, relaxing winds and clear skies will set up the potential
for another night of patchy fog development. Lows will be warmest
at the coast (mid 70s) due to the lingering onshore winds. Inland
areas will fall to the upper 60s and low 70s again.

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

&&

.SHORT TERM...(Sunday through Monday night)

Dry and quiet conditions will continue during the later half of
the weekend and into the upcoming work week as high pressure and
dry air (PWATs <=1.5") sits over the region. Northeasterly flow
will begin to weaken through the day on Sunday and shift to become
easterly by Monday. With the shift of the winds, the coastal
advisory will stay in effect through the afternoon on Sunday. The
onshore flow may bring some showers on Sunday afternoon for
coastal locations south of St. Augustine and towards the inland
locations in north central FL. Otherwise, patchy to areas of fog
is expected for far inland locations as clear skies and weak
overnight winds during the overnight hours heading into Sunday.
Temperature highs for this weekend will be in the mid to upper 80s
along the coast, with highs in the lower 90s for inland
locations. Overnight lows expected to be in the upper 60s for
locations across SE GA and in the lower 70s across NE FL.

&&

.LONG TERM...(Tuesday through Friday)

The dry weather will continue through the first half of the
upcoming work week, as dry air (PWATs <1.2") and high pressure
will remain over the region. An easterly- southeasterly flow will
allow for breezy winds along the coast. By midweek, some moisture
is expected to begin to return to the area, coming from the south-
southeast. The question still remains for the potential
development (60% chance of formation over the next 7 days from the
NHC) of a tropical system over the Gulf of Mexico and where the
system would track. Use this weekend to restock supply kits and
review family evacuation plans. Monitor official tropical
forecasts from the National Hurricane Center at hurricanes.gov and
local emergency management officials.

&&

.AVIATION...
(12Z TAFS)
Issued at 722 AM EDT Sat Sep 21 2024

MVFR VSBYS in fog will continue at GNV/VQQ until the 13-14Z time
frame, otherwise mainly VFR conds in increasing NE Flow the rest
of the morning hours with SCT Cu developing in the 2000-3000 ft
range, which could briefly become BKN MVFR CIGS in the 13-16Z time
frame, but chances remain too low or brief to include at this
time. NE winds will increase to 12-14 knots for the coastal TAF
sites today and 10-11 knots for inland TAF sites with some peak
gusts around 20 knots at times. The NE flow will bring showers in
the vicinity of the SGJ TAF site, but chances remain too low to
include TEMPO groups at this time, but will continue to monitor.
Later in the TAF period expect NE winds to diminish after sunset
and another round of MVFR fog will be possible starting at VQQ by
06Z and at GNV by 09Z.

&&

.MARINE...

High pressure building from the north will usher a brief surge of
northeast winds across the waters today and elevate seas; small
craft are urged to exercise caution. A weaker pressure pattern
will begin Sunday and continue through the middle of next week as
high pressure extends to the east. Late next week, an area of
disturbed weather in the western Caribbean may develop into a
broad tropical system as it tracks northward into the Gulf of
Mexico. Interests are urged to monitor the National Hurricane
Center for forecasts and updates with the potential tropical
disturbance next week.

RIP CURRENTS...A "mini" surge of northeasterly flow will elevate
surf and increase rip current risk to High this afternoon at all
beaches. Winds will ease up tonight but continue onshore resulting
in a Moderate Risk on Sunday.

&&

.HYDROLOGY...

A Coastal Flood Advisory continues for the St Johns River basin
(including the Intracoastal Waterway) and Atlantic coast of NE FL
through at least the next three high tide cycles. Localized areas
of low-end Moderate tidal flooding will be possible with this
early afternoon`s high tide within the St Johns River between the
Buckman Bridge and Mayport, including the Trout River. Lowering
astronomical tidal departures and weakening onshore flow will
lower tidal levels early next week.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  88  66  90  69 /   0   0   0   0
SSI  83  72  85  73 /   0   0   0   0
JAX  86  69  88  72 /   0   0   0   0
SGJ  85  74  86  74 /  10  10  10   0
GNV  89  68  90  70 /   0   0  10   0
OCF  90  70  92  72 /  10   0  10   0

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Coastal Flood Advisory until 5 PM EDT Sunday for FLZ033-038-124-
     125-132-133-137-138-225-325.

     High Rip Current Risk from 11 AM EDT this morning through this
     evening for FLZ124-125-133-138.

GA...Coastal Flood Advisory until 5 PM EDT Sunday for GAZ154-166.

     High Rip Current Risk from 11 AM EDT this morning through this
     evening for GAZ154-166.

AM...None.
&&

$$