587
FXUS62 KJAX 040546
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
146 AM EDT Tue Jun 4 2024

...New AVIATION...

.UPDATE...
Issued at 952 PM EDT Mon Jun 3 2024

Late evening surface analysis depicts Atlantic high pressure (1023
millibars) centered near Bermuda, with this feature extending its
axis westward across our region. Aloft...flat ridging prevails
over the eastern United States downstream of a potent shortwave
trough that was progressing across the Plains States. Only
isolated, low-topped convection has developed along the Interstate
75 and U.S. Highway 441 corridors this afternoon and evening as a
result of the collision of the Atlantic and Gulf coast sea breeze
boundaries. Otherwise, pockets of mid and high altitude debris
clouds were migrating eastward across our region. Temperatures
have generally fallen to the 75-80 degree range as of 02Z, with
dewpoints remaining in the 60s nearly area-wide.

Isolated low-topped convection lingering near the Suwannee and
Alapaha Rivers will dissipate before midnight. Occasional mid and
high altitude cloud cover will continue to drift overhead
overnight, with decoupling winds at inland locations and a dry,
subsident air mass allowing for lows to again fall to the mid and
upper 60s, with a light south-southeasterly breeze at coastal
locations keeps lows generally in the lower 70s.

&&

.SHORT TERM...
(Tuesday through Wednesday night)
Issued at 201 PM EDT Mon Jun 3 2024

High pressure will be located to the east northeast on Tuesday. This
will yield a flow from the east southeast. Convection will largely
be diurnally driven Tuesday, with this activity spreading west
through the afternoon.

The high will move a little more to the east northeast Wednesday,
allowing the flow over the area to come more from the south.
Convection will be largely diurnally driven, with the sea breeze
interactions aiding in the activity. A secondary max in activity
will be possible late in the afternoon between I95 and I75, as the
east coast sea breeze moves inland to meet the Gulf sea breeze.

Tuesday night and Wednesday night periods are expected to be dry
after midnight.

Temperatures will trend a little above normal this period.

&&

.LONG TERM...
(Thursday through next Monday)
Issued at 201 PM EDT Mon Jun 3 2024

Thursday will be an active convective day, as the combination of
moist southwest flow and sea breeze interactions, combines with
convergence ahead of an approaching cold front from the northwest.
This front will pass southeast across the area Thursday night. A
secondary front will move southeast across the area Friday into
Friday night with convective chances mainly driven by convergence
along the boundary.

Long range models largely depict a dry period over the weekend, as a
high pressure ridge builds to the northwest. Can not completely rule
out convection over the weekend, as boundary will linger to the
east, and diurnally driven activity will be possible.

Weak ridging will be over the area into Monday, with low end chances
for convection driven by diurnal instability.

Temperatures will be above normal throughout this period. While
temperatures will still be quite warm Saturday and Sunday following
frontal passage, it will not be as humid with dewpoints generally
falling into the 55 to 65 range.

&&

.AVIATION...
(06Z TAFS)
Issued at 145 AM EDT Tue Jun 4 2024

Though periods of MVFR ceilings at the immediate coast are
possible until sunrise, predominant conditions will be VFR through
the period. There will be a chance of isolated VCSH/VCTS this
afternoon but that activity will be spotty in nature. KGNV may be
the only airfield deserving of a prevailing/TEMPO TS group during
the late afternoon but confidence is too low to include at this
time. The Atlantic sea breeze will be progressive once again today
and push into KJAX by 16z/17z with wind speeds around 10-13 kts
as it continues westward through the rest of the afternoon. No
significant fog development is likely, though typical "swamp" fog
is possible this morning at KVQQ. &&

.AVIATION...
(00Z TAFS)
Issued at 818 PM EDT Mon Jun 3 2024

Isolated showers may develop around the GNV terminal through
around 03Z this evening. Otherwise, periods of IFR visibilities
are expected at VQQ during the overnight and predawn hours. VFR
conditions will otherwise prevail at the regional terminals.
Isolated to widely scattered showers and thunderstorms will
develop after 16Z Tuesday, mainly for locations to the west of
Interstate 95. Confidence was only high enough to include vicinity
thunderstorms at GNV after 21Z, where the Atlantic and Gulf coast
sea breezes will likely collide nearby during the late afternoon
and early evening hours. Confidence was otherwise only high enough
for vicinity shower coverage at the Duval County terminals, while
the SSI and SGJ coastal terminals likely remaining dry through the
period. South-southeasterly surface winds sustained around 10
knots early this evening will shift to southerly while diminishing
overnight. Light southerly surface winds will resume after sunrise
and will then shift to east-southeasterly by early afternoon on
Tuesday as the Atlantic sea breeze boundary moves inland, with
sustained speeds increasing to 10-15 knots after 16Z at the
coastal terminals and around 10 knots at the inland terminals
after 18Z.

&&

.MARINE...
Issued at 952 PM EDT Mon Jun 3 2024

Atlantic high pressure centered near Bermuda will continue to
extend its axis westward across our local waters on Tuesday,
keeping a prevailing southeasterly wind flow across our local
waters. Southerly evening wind surges are expected through
midweek, with onshore winds strengthening each afternoon near
shore. Wind speeds are expected to remain around or just below
Caution levels during these wind surges, with seas of 2-3 feet
prevailing both near shore and offshore during the next several
days.

Atlantic high pressure will gradually weaken by midweek and
will then shift eastward as a trough dives into the southeastern
states. Chances for mainly afternoon and evening showers and
thunderstorms will increase ahead of this approaching trough on
Wednesday and Thursday. A weak cold front will then move across
our local waters on Friday evening, preceded by scattered showers
and thunderstorms. Weak high pressure will then settle over the
southeastern states in the wake of this frontal passage during the
upcoming weekend.

Rip Currents: Breezy onshore winds developing each afternoon will
combine with a weak east-southeasterly ocean swell to keep a
moderate rip current risk in place at all area beaches through
midweek. Prevailing offshore winds and low wave heights will
likely result in a low rip current risk on Thursday and Friday.

&&

.FIRE WEATHER...
Issued at 952 PM EDT Mon Jun 3 2024

A dry air mass will persist across our region on Tuesday,
resulting in minimum relative humidity values falling to around
35 percent at most inland locations. Light southeast to southerly
surface and transport winds on Tuesday morning will shift to east-
southeasterly for locations east of U.S. Highway 301, with breezy
surface winds developing during the afternoon hours along the
Interstate 95 corridor, where fair to good daytime dispersion
values are expected. Lighter southerly transport winds elsewhere
well inland will combine with elevated mixing heights to result in
generally fair daytime dispersion values on Tuesday afternoon.
Southerly transport winds on Wednesday morning will shift to
southwesterly during the afternoon hours, with breezy speeds
developing for locations along and north of the I-10 corridor
during the afternoon hours. These breezy conditions will combine
with elevated mixing heights to create good to marginally high
daytime dispersion values on Wednesday afternoon. Lighter speeds
south of I-10 will generally result in fair daytime dispersion
values. Breezy westerly transport winds on Thursday will combine
with elevated mixing heights to create high daytime dispersion
values across much of our area.

&&

.CLIMATE...
Issued at 952 PM EDT Mon Jun 3 2024

Record high temperatures at our designated climate sites on
Thursday and Friday:

                June 6      June 7
              ----------------------
Jacksonville    99/1985    100/1993
Gainesville     100/1927   99/1985
Alma, GA        101/1985   98/1993
Craig Airport   99/2011    96/1985

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  92  69  92  71 /  50  30  50  20
SSI  89  74  91  76 /  10  10  30  20
JAX  91  69  92  71 /  20  10  50  20
SGJ  88  73  92  74 /  10  10  40  20
GNV  94  69  93  70 /  40  20  50  30
OCF  95  69  94  71 /  30  20  50  20

&&

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

$$