648
FXUS62 KJAX 120618
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
218 AM EDT Wed Jun 12 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...
(06Z TAFS)
Issued at 219 AM EDT Wed Jun 12 2024

Low MVFR ceilings of 1,000 - 1,500 feet are expected to develop
at GNV and VQQ after 08Z, with periods of IFR ceilings possible
around sunrise. MVFR ceilings of 2,000 - 3,000 feet are forecast
to develop after 12Z at SGJ, with periods of MVFR ceilings
possible at the Duval County terminals and SSI during the morning
hours. Confidence was too low to indicate anything other than
scattered ceilings at the Duval County terminals and SSI at this
time. Ceilings are expected to lift to VFR at the regional
terminals by 18Z. Showers and thunderstorms will develop during
the mid to late afternoon hours at the northeast FL terminals,
with activity increasing in coverage and intensity along the
Interstate 75 corridor during the late afternoon hours, and
confidence was high enough to include a PROB30 group at GNV after
19Z through 00Z, with IFR visibilities possible during heavier
downpours, along with brief wind gusts up to 30 knots. Showers
will begin to move onshore from the Atlantic waters towards the
end of this TAF period, possibly impacting the SSI and SGJ coastal
terminals as well as the Duval County terminals overnight. Light
southerly surface winds overnight at the northeast FL terminals
will shift to easterly after sunrise. Meanwhile, light easterly
winds overnight at SSI will shift to northeasterly towards
sunrise, with speeds increasing to around 15 knots and gusty after
15Z. Surface winds will shift to northeasterly at the rest of the
terminals after 17Z, with speeds increasing to 10-15 knots outside
of thunderstorm activity during the afternoon hours.

&&

.UPDATE...
Issued at 710 PM EDT Tue Jun 11 2024

A frontal boundary, extending from broad low pressure area over
Gulf, will lay northeast across forecast area Tonight. With loss
of diurnal best convective chances will end this evening, but a
few showers could still pop up during the overnight given ample
moisture and frontal convergence.

Lows Tonight will range from the lower 70s inland, to the upper 70s
along the coast.

&&

.SHORT TERM...
(Wednesday through Thursday night)
Issued at 213 PM EDT Tue Jun 11 2024

An area of low pressure develops into a closed low as it moves
northeastward along the stalled boundary draped across NE FL and
exits into the coastal Atlantic waters by Wednesday night. Model
differences continue with the ECMWF as the faster solution with a
closed low emerging into the Atlantic Wednesday morning and then
weakening as it shifts further into the Atlantic. The GFS lags
behind the other models but further strengthens the low on
Thursday as it meanders along the boundary into the Atlantic. At
this time, the environment remains unfavorable for tropical
development and so NHC has highlighted only a low chance for
development. Showers and thunderstorms develop mainly across NE FL
on Wednesday as the low pressure spreads tropical moisture (PWATs
2+ in) across NE FL. Flow becomes northeasterly with the low in
the western Atlantic and filters in some drier air into SE GA for
Thursday. Rain chances will be slightly lower for Thursday. Deep
tropical moisture remains over north-central FL where 1-3 in. of
rainfall will be possible Wednesday into Thursday. Rain and cloud
cover will keep the heat at bay with highs in the upper 80s to low
90s and overnight lows in the 70s.

&&

.LONG TERM...
(Friday through next Tuesday)
Issued at 213 PM EDT Tue Jun 11 2024

The subtropical jet aloft and surface boundary will remain positioned
just to the south of our region through Friday, which should keep
the majority of the higher mean layer moisture to our south and
therefore lower chances for convection. By the weekend, surface
high pressure over the northeastern US shifts offshore and induce
a more easterly onshore flow over the region. Although this will
increase available moisture in the lower levels, high pressure
also looks to build in/strengthen aloft which will result in some
increase in subsidence in the upper levels. Given the time of
year, will likely still be chances for showers and t`storms
diurnally daily for the weekend and into Monday, though chances
look lower than average as of now. Guidance has been suggesting an
elongated trough like feature from the Caribbean into the western
Gulf around the start of next week, though higher pressure
overhead should help to keep the feature suppressed well to the
west of the area.

Regarding temperatures: Temps will be slightly above average for
Friday and into Saturday, though tending closer to normal by
Sunday and into the start of next week with the increasing onshore
flow.

&&

.MARINE...
Issued at 213 PM EDT Tue Jun 11 2024

The frontal boundary will remain stalled across our local waters
today, with showers and thunderstorms initially over central
Florida gradually spreading northward towards our area this
afternoon. Weak low pressure will then develop along this stalled
boundary tonight over the northeast Florida waters, with this
feature moving slowly northeastward through Friday. Prevailing
onshore winds are expected late this week as this weak low
pressure center moves further away from our local waters. Periods
of showers and thunderstorms will remain possible across through
the upcoming weekend as the frontal boundary remains stalled. A
stronger high pressure center will build southeastward from the
eastern Great Lakes region this weekend, with a surge of onshore
winds possible by Sunday and Monday as this feature wedges down
the southeastern seaboard.

Rip Currents: Developing onshore winds this afternoon will combine
with a south-southeasterly ocean swell to create a low-end
moderate rip current risk at area beaches. This lower end moderate
risk will likely continue during the next few days.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  92  70  92  69 /  10  10  20  10
SSI  87  76  87  75 /  20  10  30  20
JAX  90  72  90  71 /  40  10  40  20
SGJ  89  75  88  73 /  50  30  60  30
GNV  91  71  91  69 /  80  30  50  20
OCF  90  72  90  71 /  80  60  60  40

&&

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

$$