553
FXUS62 KJAX 081915
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
315 PM EDT Wed May 8 2024

...NEAR RECORD HIGHS CONTINUE THROUGH THURSDAY...
...SQUALL LINE OF STRONG TO SEVERE THUNDERSTORMS POSSIBLE LATE ON
THURSDAY AFTERNOON AND EVENING FOR LOCATIONS NORTH OF I-10...
...STRONG TO ISOLATED SEVERE STORMS POSSIBLE ON FRIDAY...

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

.SYNOPSIS...
Issued at 315 PM EDT Wed May 8 2024

Early afternoon surface analysis depicts Atlantic high pressure
(1020 millibars) centered to the south of Bermuda, with this
feature extending its axis westward across the FL peninsula.
Meanwhile, a wavy surface front extends from New England and the
Mid-Atlantic states westward across the Great Lakes states and
then southwestward across the Plains States and the Desert
Southwest. Aloft...ridging centered over the Yucatan Peninsula
continues to build northeastward across the Gulf of Mexico and
across the FL peninsula. Otherwise, a blocking pattern was in
place over the Rockies and Plains states, while a potent shortwave
trough was progressing east-southeastward across eastern portions
of the Great Lakes towards New England. A healthy cumulus cloud
field was in place across our region. Temperatures at 19Z ranged
from the mid 80s along the immediate coast to the upper 80s and
lower 90s at inland locations. Dewpoints were generally in the 60s
at inland locations, ranging to the lower 70s at coastal
locations.

&&

.NEAR TERM...
(through Tonight)
Issued at 315 PM EDT Wed May 8 2024

Breezy southwesterly winds in the boundary later overnight will
likely advect another stratus layer inland from the northeast Gulf
of Mexico across the Suwannee Valley and inland southeast GA after
midnight, with this stratus layer then potentially shifting
eastward across U.S. Highway 301 during the predawn hours. Lows
tonight will only fall to the upper 60s and lower 70s area-wide.

&&

.SHORT TERM...
(Thursday through Friday night)
Issued at 315 PM EDT Wed May 8 2024

Breezy southwest winds will be in place ahead of a cold front
moving south to the area. Ahead of the cold front, a line of
showers and storms will begin to move across the area on Thursday
afternoon/evening. With the latest update, SPC has placed areas
north of Waycross, GA into an Enhanced Risk (level 3 out of 5) for
severe thunderstorm development, with the primarily concern of
damaging wind gusts (with gusts from 50-70 mph), along with Hail
up to 1" as well as the possibility of isolated tornadoes as the
line of storms moves through SE GA into NE FL. Storms will begin
to move offshore by the early evening hours, allowing for a
respite from the more severe storms during the overnight hours.

By Friday morning, activity will begin to increase as the cold
front begins to move across the area. The majority of the area
will be in a Marginal Risk (1 out of 5) for severe thunderstorm
development, again damaging wind gusts will be the main concern
for storms that do develop. Activity will begin to dwindle as
evening arrives, as the cold front will have move through to the
south of NE FL.

Before the cold front`s arrival, Thursday`s daytime temperatures
will again reach near record levels as most areas will see daytime
highs in the mid 90s, leading to Heat Index values ranging from
the mid 90s to 100s. Temperatures will trend down a bit on Friday
as the front begins to move through the area, locations north of
the I-10 corridor will top out in the mid to upper 80s, while
locations along the St. Johns River Basin will top out in the
lower 90s.

&&

.LONG TERM...
(Saturday through next Wednesday)
Issued at 315 PM EDT Wed May 8 2024

The weekend will be marked by a quiet weather pattern with high
pressure beginning to build into the area after the cold front`s
passage. The next round of activity currently looks to move in
during the early portion of the following week as high pressure
begins to weaken over the area.

The cold front will usher in cooler temperatures through the
weekend and into next week, as daytime temperatures will be in the
upper 70s to lower 80s over SE GA and from the lower 80s to upper
80s.

&&

.AVIATION...
(18Z TAFS)
Issued at 235 PM EDT Wed May 8 2024

VFR conditions will prevail at the regional terminals through at
least 06Z Thursday. Low stratus ceilings are expected to
overspread GNV by 09Z Thursday, with IFR conditions possible.
However, confidence was too low to include anything lower than
1,000 foot ceilings at this time. Low MVFR ceilings are likely to
continue through around 14Z at GNV. MVFR visibilities are likely
to develop overnight through around sunrise at VQQ, with periods
of IFR conditions possible during the predawn hours on Thursday.
Confidence was too low to include prevailing IFR conditions at VQQ
at this time. There is a low possibility of a brief period of
MVFR ceilings after sunrise on Thursday at the rest of the
terminals, but VFR conditions are expected to prevail at the
regional terminals before 15Z Thursday. The Atlantic sea breeze
boundary will continue to move slowly inland towards and then
across Interstate 95 during the mid to late afternoon hours.
Southeasterly surface winds of 10-15 knots are expected to
continue at the SSI and SGJ coastal terminals through around 00Z,
with southwesterly surface winds of 10-15 knots elsewhere, except
at CRG and JAX terminals, where winds will shift to southeasterly
by 22Z as the Atlantic sea breeze pushes westward. Surface winds
will then shift to southerly after sunset, with speeds generally
diminishing to 5-10 knots by 03Z. Southwesterly surface winds will
then quickly increase after sunrise on Thursday, with sustained
speeds increasing to 10-15 knots before 15Z.

&&

.MARINE...
Issued at 315 PM EDT Wed May 8 2024

Atlantic high pressure will continue to extend its axis westward
across the Florida peninsula through Thursday night. Southerly
evening wind surges are expected this evening and again on
Thursday evening, bringing wind speeds up to Caution levels of 15
to 20 knots for the offshore waters. Seas of 2-4 feet will prevail
through Thursday night for the near shore waters, with 3-5 foot
seas prevailing offshore.

Meanwhile, a strong cold front will enter the southeastern states
on Thursday night, with chances for showers and thunderstorms
increasing ahead of this boundary from Thursday afternoon through
Friday evening. A few rounds of strong to severe thunderstorms
will be possible during this time frame, with damaging wind gusts,
hail, and frequent lightning strikes possible within any severe
thunderstorms that develop. The cold front will cross our local
waters on Friday afternoon and evening, with high pressure then
gradually building to the north of our area later this weekend and
early next week in the wake of this frontal passage, resulting in
prevailing onshore winds during this time period. Seas of 2-4 feet
will prevail both near shore and offshore from Friday through the
weekend.

Rip Currents: Breezy onshore winds developing this afternoon and
again on Thursday afternoon will combine with a northeasterly
ocean swell to create a moderate rip current risk at all area
beaches on both afternoons. Breezy offshore winds on Friday should
reduce the risk to low at all area beaches.

&&

.FIRE WEATHER...
Issued at 315 PM EDT Wed May 8 2024

Southwesterly transport winds will strengthen further on Thursday,
creating high daytime dispersion values for most locations east
of the Interstate 75 corridor during the afternoon hours.
Otherwise, a hot and dry air mass over our region will result in
minimum relative humidity values falling to around 35 percent at
most inland locations this afternoon, with minimum values again
around 35 percent forecast for most locations east of I-75 on
Thursday afternoon. Strong west-southwesterly transport winds on
Friday will again create good to marginally high daytime
dispersion values, except for high values across portions of
north central FL. A few rounds of strong to severe thunderstorms
will be possible from Thursday afternoon through Friday evening,
with damaging wind gusts, hail, and frequent lightning strikes
possible within any severe thunderstorms that develop. Surface and
transport winds will shift to northwesterly on Saturday, with a
cooler and drier air mass dropping relative humidity values to the
30-35 percent range at inland locations on Saturday afternoon.

&&

.CLIMATE...
Issued at 1232 PM EDT Wed May 8 2024

Daily record Maximum Temperatures at the local climate sites for...

Today, May 8th...JAX 96/1959...CRG 93/1977...GNV 97/1955...AMG 95/1962

Thursday, May 9th...JAX 96/1962...CRG 93/2008...GNV 95/2011...AMG 95/1962

Friday, May 10th...JAX 94/2017...CRG 95/2003...GNV 95/2011...AMG 95/2011

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  69  92  72  85 /  10  40  40  80
SSI  74  93  74  86 /   0  20  40  80
JAX  70  95  73  89 /   0  10  20  80
SGJ  73  95  73  91 /   0  10  10  70
GNV  70  92  72  88 /   0  10  10  80
OCF  71  92  73  89 /   0   0  10  60

&&

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

$$