115
FXUS62 KJAX 121733
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
133 PM EDT Wed Jun 12 2024

...New AVIATION...

.UPDATE...
Issued at 1021 AM EDT Wed Jun 12 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

The tropical low will pass to our south with some convection
likely firing to it`s north, just south of an old surface front.
So the best likelihood for convection will be south of a line from
Matanzas Inlet to Gainesville to Trenton. Best chance of
precipitation will be from about 3 p.m. through 9 p.m. Later
tonight, as the low passes offshore it will try to consolidate
and we might see some showers and thunderstorms over the coastal
waters. Updated the probability of Precipitation across the
southern areas and slightly increased the POPS.

&&

.SYNOPSIS...
Issued at 418 AM EDT Wed Jun 12 2024

Early morning surface analysis depicts the center of Invest 90L
(1008 millibars) drifting northeastward across Tampa Bay.
Meanwhile, a stationary frontal boundary was draped from the
northern Gulf coast eastward along the Interstate 10 corridor.
Otherwise, weak high pressure (1018 millibars) was building
southward down the Appalachians mountains. Aloft...deep troughing
was slowly moving northeastward across New England, with westerly
flow in place locally downstream of a shortwave trough that was
progressing east-southeastward across the Ozarks and the lower
Mississippi Valley. Latest GOES-East derived Total Precipitable
Water imagery indicates that deep tropical moisture remains in
place for locations along and south of the stalled frontal
boundary, where PWAT values ranged from 1.8 - 2.0 inches, while a
much drier air mass remains in place across inland portions of
southeast GA, where PWAT values were generally in the 1.2 - 1.5
inch range. Pockets of low and mid level clouds were moving
northward from central FL into north central FL, with higher
altitude cloud cover in place across most of southeast GA.
Temperatures and dewpoints at 08Z were mostly in the 70s, except
at coastal locations, where temperatures remain around 80 degrees
at area beaches.

&&

.NEAR TERM...
(Today and Tonight)
Issued at 418 AM EDT Wed Jun 12 2024

Low stratus cloud cover and pockets of fog may expand somewhat
this morning, especially across north central FL. These lower
clouds should dissipate by the early to mid-morning hours.
Otherwise, low pressure will migrate northeastward along the
Interstate 4 corridor today, emerging off the FL Atlantic coast
near Daytona Beach this evening. Deep tropical moisture will
remain in place today for locations south of the Interstate 10
corridor, where convection should begin to develop later this
morning and this afternoon. Meanwhile, high pressure centered over
the Appalachians this morning will briefly wedge down the
southeastern seaboard today, creating a tightening local pressure
gradient across our region that will result in east-northeasterly
winds strengthening and becoming breezy from north to south along
the I-95 corridor and points eastward today.

These northeasterly winds will reinforce the already dry air mass
across southeast GA, and this flow will focus a more widespread
area of convection along the I-75 corridor late this afternoon and
into the evening hours as mesoscale boundaries collide within a
seasonably moist air mass along and south of the stalled frontal
boundary. Pulsing, slow moving convection may again result in
localized flooding later today, especially for urban locations
such as Gainesville and Ocala, where 1-3 inches of rainfall may
occur in a short period of time on a localized basis. Merging and
pulsing convection may result in a few briefly stronger storms
that will be capable of producing downburst winds of 40-50 mph and
frequent lightning strikes. Breezy onshore winds this afternoon
will keep coastal highs generally in the upper 80s, while inland
highs mostly reach the lower 90s, with a few mid 90s possible in
the Suwannee Valley.

Low level convergence will strengthen tonight as Invest 90L moves
slowly northeastward across the Gulf Stream waters adjacent to
northeast FL. These onshore winds may begin to advect showers and
possibly some lower topped convection onshore along the I-95
corridor during the overnight hours. Otherwise, evening convection
will wind down before midnight along the I-75 corridor, with
patches of lower stratus and fog possibly developing during the
predawn hours at locations that receive heavier downpours later
today. Lows tonight will generally fall to the 70-75 degree range
area-wide.

&&

.SHORT TERM...
(Thursday through Friday night)
Issued at 418 AM EDT Wed Jun 12 2024

The area of broad low pressure will have made its way off the FL
coast by early Thursday morning, remaining at a low chance of
any development due to a non favorable environment. Main focus for
this forecast period will be the increase chances of showers and
thunderstorms during the afternoon hours for both days for
locations south of the stalled frontal boundary in north central
Florida. Marginal risk for excessive rainfall by the WPC remains
for southern areas of Marion County on Thursday.

Daytime temperature highs will begin sit in the lower 90s for much
of the local area, with southern Marion County and coastal areas
dipping to the mid to upper 80s. Overnight lows will see
temperatures sit in the lower 70s across inland locations and in
the mid 70s along the coast.

&&

.LONG TERM...
(Saturday through Tuesday)
Issued at 418 AM EDT Wed Jun 12 2024

With the frontal boundary finally making its way out of the local
area, in addition to the broad area of low pressure lifting off
towards the northeast, chances of showers and thunderstorms should
begin to lessen from the past couple of day. Enough moisture may
persist over the area to allow for afternoon showers and storms to
develop during the weekend and into the upcoming week.
Temperatures will look to rise to warmer than average levels
during the early portion of the weekend before more seasonal
levels become established as the Atlantic sea breeze will bring in
cooler air.

&&

.AVIATION...
(18Z TAFS)
Issued at 127 PM EDT Wed Jun 12 2024

A few showers and thunderstorms are developing near the
Jacksonville Metro area and also over the coastal waters east of
Jacksonville Beach. The offshore storms are slowly working their
way back toward the coast and thus have introduced tempo groups
for the Jacksonville Metro Fields. Otherwise not much has changed
with the thinking for today as our tropical low passes south of
our area and high pressure builds in to our north.The pressure gradient
between the two will keep winds from the ENE and they gusty into
the evening hours, dropping off a bit after sunset.


&&

.MARINE...
Issued at 1021 AM EDT Wed Jun 12 2024

A weak tropical low will pass offshore this evening and try to
consolidate as it moves further east. See the latest NHC outlook
for details on the low. High pressure to our north will increase
the pressure gradient across the coastal waters generating some
stronger northeast to east winds over the next few days.

Rip Currents: |Onshore winds will become breezy from north to south
today along our coast, generating a moderate rip current risk by
this afternoon for all area beaches. This moderate risk will
likely continue through Friday as a northeasterly ocean swell
develops in the wake of a departing low pressure center.

&&

.FIRE WEATHER...
Issued at 418 AM EDT Wed Jun 12 2024

East-northeasterly surface and transport winds will gradually
strengthen today, creating fair to good daytime dispersion values.
Locally heavy downpours are expected late this afternoon and early
this evening along the Interstate 75 corridor as thunderstorms
increase in coverage. Breezy northeasterly transport winds on
Thursday will create good to marginally high daytime dispersion
values across southeast GA and northern portions of the Suwannee
Valley, with cloud cover keeping values generally fair for
locations south of Interstate 10. Northeasterly surface and
transport winds will begin to weaken on Friday, but elevated
mixing heights will result in marginally high daytime dispersion
values across inland portions of southeast GA and northern
portions of the Suwannee Valley, with fair to good values expected
elsewhere.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  91  70  93  69 /  20  10  20  10
SSI  87  75  87  75 /  20  30  40  20
JAX  91  72  90  72 /  30  40  60  20
SGJ  89  75  89  74 /  40  30  70  40
GNV  92  72  91  69 /  60  40  70  30
OCF  92  72  90  72 /  80  60  80  50

&&

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

$$