092
FXUS62 KJAX 021228
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
828 AM EDT Tue Jul 2 2024

...New AVIATION...

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

.AVIATION...
(12Z TAFS)
Issued at 829 AM EDT Tue Jul 2 2024

VFR conditions will prevail at the regional terminals through at
least 16Z. Isolated showers may develop near SSI and the Duval
County terminals this morning, with brief periods of MVFR ceilings
possible. Showers and thunderstorms will then develop along the
Interstate 95 corridor along the inland moving Atlantic sea breeze
boundary shortly after noon. PROB30 groups were maintained through
the afternoon hours at SSI and the Duval County terminals, with
lower confidence for impacts at SGJ, where vicinity coverage was
used at the PROB30 group was eliminated. Higher probabilities for
IFR impacts and brief wind gusts around 30 knots are expected
late this afternoon through early this evening at VQQ and GNV,
where the Atlantic and Gulf coast sea breezes will collide towards
sunset tonight along the U.S. Highway 301 corridor. PROB30 groups
were maintained at these two terminals through around 02Z for
now, but will likely be upgraded to TEMPO groups for the 18Z TAF
package. Thunderstorm coverage at the inland terminals should
dissipate before 04Z, with MVFR visibilities likely to develop at
VQQ before 06Z. VFR conditions should otherwise prevail overnight
at the regional terminals. Light and variable winds through around
14Z will shift to southeasterly before noon, with speeds outside
of thunderstorm activity expected to remain in the 5-10 knot range
at the inland terminals, with speeds increasing to around 10 knots
at the SGJ and SSI coastal terminals after 17Z.

&&

.NEAR TERM...
(Today through Tonight)
Issued at 415 AM EDT Tue Jul 2 2024

Weakening frontal boundary will remain stalled over Georgia today
as high pressure shifts eastward towards the Atlantic. Prevailing
flow will shift to become more out of the southeast through today
and tonight with moist conditions holding ahead of the front with
PWAT values measuring between about 2.2 and 2.6 inches. Showers
and storms will form with the diurnal eastern sea breeze initially
along and to the west of the I-95 corridor and press inland as
the afternoon progresses. Strongest developments will occur along
boundaries and areas of collision with storms being capable of
producing heavy localized rainfall due to the moisture heavy air
mass. Convection will become dispersed in the evening and overnight
hours with drier conditions carrying over into the next day. High
temperatures today will rise into the lower to mid 90s for most
inland areas and in the upper 80s along the coast and for portions
of SE Georgia situated behind the frontal boundary. Overnight low
temperatures are expected to drop down into the mid 70s for
inland areas and in the upper 70s and lower 80s along the coast.
Heat index values will rise to be above 100 degrees today but are
not expected to reach Heat Advisory levels this afternoon.

&&

.SHORT TERM...
(Wednesday through Thursday night)
Issued at 415 AM EDT Tue Jul 2 2024

Weak, nearly stationary frontal boundary lays generally west to
east across eastern GA on Wednesday and will briefly be stalled.
Sfc high pressure will gradually build north of the boundary by
Thursday helping to push the diffuse boundary southward into
northeast FL. Mid to upper level ridge will be parked over the
southeast states Wednesday through Wednesday night and then
slightly retrograde on Thursday as some mid level troughing drops
in over SC and eastern GA. PWATs are still forecast to remain
elevated at about 2 to 2.3 inches on Wednesday with mean steering
flow from the east but only at 5-10 knots. With sea breezes,
daytime heating, and the weak frontal boundary, numerous showers
and thunderstorms are expected Wed and will fade in coverage Wed
night. Locally heavy rainfall and gusty winds expected with the
stronger storms mainly inland areas, given the push of the
easterly flow moving storms inland.

Thursday, shower and storm coverage remains in the scattered to
numerous range with the frontal boundary shifting southward, and
the axis of higher precip chances drifting southward as well. The
lighter synoptic flow and PWATs of at least 2 inches will support
locally heavy rainfall/localized flooding. Some drier air will
likely be working in from the northeast late Thu into Thur night
as the mid level trough from SC pushes deeper moisture further
southward.

High temps both Wed and Thu expected in the lower 90s most areas
with heat indices topping out around 104-108, so near or just
below heat advy criteria. This will need to be monitored but at
this time not enough area to indicate advisories would be
warranted. Lows generally in the mid 70s given the soupy airmass
and debris clouds from daytime convection.

&&

.LONG TERM...
(Friday through Monday)
Issued at 415 AM EDT Tue Jul 2 2024

Mid to upper layer ridging will prevail over the area Friday through
the weekend, with some drier air continuing to work into the area
from the east and northeast Friday and Saturday. The mid level ridge
will shift southeastward on Monday as mid level troughing drops
into the Great Lakes and most of the MS valley area. Sfc ridge
will be across north central FL area Friday and slowly shift
southward over the weekend and into Monday. Sea breezes and
daytime heating expected to support generally just scattered
showers and storms each day, but drier air Fri and Sat and warm
temps aloft could potential result in just widely scattered
(25-30 percent) coverage. Best coverage of storms looks to be
near and west of Highway 301 over northeast FL Friday through
Sunday. A slight uptick in rain chances for most zones is
indicated for Monday as deep moisture levels rise over the area.
Ridging and drier air will allow high temperatures to quickly rise
into the mid/upper 90s through the weekend. Heat indices will
likely rise into heat advisory criteria by the weekend.

&&

.MARINE...
Issued at 415 AM EDT Tue Jul 2 2024

The frontal boundary stalled over local Georgia waters will begin to
dissipate, with increasing chances for mainly afternoon and
nighttime showers and thunderstorms across our local waters.
Prevailing winds will shift to east and southeast today through
Wednesday as high pressure builds down the southeastern seaboard.
High pressure will then weaken as it shifts southward towards our
local waters later this week.

Rip Currents: Moderate Rip Current Risk for beaches through
Wednesday.

&&

.HYDROLOGY...
Issued at 400 AM EDT Mon Jul 1 2024

High moisture (PWATs ~2.3 inches) over the region will lead to
heavy downpours from convection especially along and ahead of an
approaching frontal boundary/trough from the north. WPC has placed
SE GA and small area of northeast FL in a marginal risk of
excessive rainfall today. Localized areas could see rain amounts
of 3 inches in a short period of time.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  88  74  91  74 /  70  40  70  20
SSI  87  78  89  78 /  60  50  50  30
JAX  91  75  91  75 /  70  50  70  30
SGJ  91  78  91  77 /  60  50  60  30
GNV  92  73  92  74 /  70  60  70  30
OCF  93  75  93  75 /  70  70  70  30

&&

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

$$