209
FXUS62 KJAX 060228
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
1028 PM EDT Sat Oct 5 2024

...LOCALLY HEAVY RAINFALL FOR THE COASTAL COUNTIES ON SUNDAY...
...ROUGH SURF AND HAZARDOUS MARINE CONDITIONS CONTINUE...
...MILTON POISED TO STRENGTHEN INTO A HURRICANE OVER THE GULF OF
MEXICO BY TOMORROW NIGHT OR MONDAY...

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

.UPDATE...
Issued at 1029 PM EDT Sat Oct 5 2024

Late evening surface analysis depicts developing Tropical Storm
Milton (1006 millibars) located over the far western Gulf of
Mexico. Closer to our area, a frontal boundary located near the
FL/GA border was drifting southward as high pressure (1026
millibars) centered near Maine wedges down the southeastern
seaboard. A coastal trough was positioned over our local Atlantic
waters, which was generating showers and a few embedded
thunderstorms, with just a few light showers or sprinkles
streaming onshore along the coastal counties. Aloft...Milton is
currently stuck between ridges over the northwestern Caribbean Se
and Baja California, while a trough was digging southeastward from
the upper Midwest towards the Great Lakes region. Temperatures
were generally in the 70s area-wide at 02Z, except around 80 at
coastal locations. Dewpoints ranged from the upper 60s over inland
southeast GA to the lower 70s elsewhere.

Ridging positioned over the northwestern Caribbean will slip
southward tonight and Sunday as troughing begins to sharpen over
the southeastern states, downstream of the longwave trough digging
across the Upper Midwest and Great Lakes states. Meanwhile,
coastal troughing will shift closer to the Atlantic coast
overnight, and another wave of showers and embedded thunderstorms
will likely push onshore during the predawn and early morning
hours along the I-95 corridor, with locally heavy downpours
possible through the morning hours in the coastal counties. Lows
tonight will generally remain in the 70s area-wide as multi-
layered cloudiness thickens.

&&

.SHORT TERM...
(Sunday through Monday night)
Issued at 230 PM EDT Sat Oct 5 2024

A pretty persistent pattern will continue to end the weekend on
Sunday, with a modest onshore flow persisting chances for showers
and perhaps some very isolated thunder, especially for the coasts
and eastern of about HWY 301 in northeast FL. Onshore flow and
plenty of clouds will keep high temps in the upper 70s to low 80s.
Showers diminish and confine mainly to waters Sunday Night, with
a noticeable decrease in cloud cover as well for interior areas
north and east. Moisture boundary aloft drops further southward
Sunday Night and into Monday and builds a surface ridge further
south into northeast FL as well, which is expected to confine rain
chances to mainly for southern portions of the area as well as
coastal northeast FL into Monday. Instability will be limited once
again Monday, and therefore expected primarily scattered showers
with very isolated thunder possible. The moisture gradient will
also influence the temperature gradient Monday, with more clouds
than sun and lower 80s south and partly to mostly sunny and low to
mid 80s north into interior southeast GA.

&&

.LONG TERM...
(Tuesday through next Saturday)
Issued at 230 PM EDT Sat Oct 5 2024

First half of this period will of course be heavily influenced by
potential impacts from Tropical Storm Milton, as the system
progresses east/northeast across the eastern Gulf to start the
week and approaches/moves across the central or southern FL
peninsula some time around mid week. Regardless of the exact track
and intensity of the system, the passage of low pressure to the
south and aforementioned ridging north of the boundary definitely
promotes blustery onshore flow winds, resulting in building
hazardous marine conditions as well as coastal flooding/tidal
flooding potential for the Atlantic Coast and St. Johns River.
With a frontal boundary across the area, this setup will also
promote periods of heavy rainfall and flooding potential during
the mid week period, with exact totals dependent on exactly where
the front settles and where Milton ends up tracking. With already
weakened trees and limbs from Helene`s impacts, the strengthening
NE winds and gusts of at least near 30 mph at times for coastal
areas and NE FL could produce additional tree damage. Be sure to
stay up to date with the latest forecasts at hurricanes.gov, and
maintain tropical readiness.

Milton`s departure brings a cooler and drier northerly flow into
the region by late in the week, with fall-like conditions (at
least for Florida standards) working their way into the area.
Breezy conditions will likely continue through the rest of the
long term post Milton however, persisting coastal, marine, and
tidal flooding hazards. High temperatures will trend near to below
normal mid-week, then falling below normal for late week,
especially across inland SE GA and the Suwannee River Valley where
driest air will intrude.

&&

.AVIATION...
(00Z TAFS)
Issued at 823 PM EDT Sat Oct 5 2024

Periods of MVFR ceilings between 1,000 - 2,000 feet are expected
at the regional terminals overnight. The next wave of showers and
possible embedded thunderstorms moving onshore from the Atlantic
waters are expected to impact SSI, JAX, CRG, and SGJ during the
predawn hours. We have placed PROB30 groups for MVFR conditions
during heavier downpours after 08Z at these terminals. MVFR
ceilings will otherwise prevail through around 13Z at VQQ and GNV.
Additional waves of showers and a few embedded thunderstorms will
impact the regional terminals through the rest of the daylight
hours on Sunday, possibly extending into Sunday evening. PROB30
groups for IFR conditions and briefly gusty winds were placed at
each terminal`s TAF, as timing and intensity remain in question
for impacts on Sunday. Generally easterly winds will remain
sustained around 10 knots outside of shower and thunderstorm
activity overnight at the SSI and SGJ coastal terminals and CRG,
with speeds further inland around 5 knots or less. Surface winds
will then shift to northeasterly towards sunrise, with speeds of
10-15 knots at the coastal terminals and 5-10 knots further inland
on Sunday.

&&

.MARINE...
Issued at 1029 PM EDT Sat Oct 5 2024

High pressure centered near Maine will continue to wedge down the
southeastern seaboard, with coastal troughing situated over our
adjacent Atlantic waters generating waves of showers and embedded
thunderstorms through Sunday. Small Craft should Exercise Caution
both near shore and offshore tonight, as speeds remain in the
15-20 knot range and seas remain in the 4-6 foot range. Meanwhile,
a frontal boundary over the Georgia waters will push southward
through the northeast Florida waters on Sunday night and Monday.
Breezy east-northeasterly winds will result in gradually building
seas, with Small Craft Advisory conditions possible over portions
of the Georgia waters by late Sunday or Sunday night as seas
build to 5-7 feet, with Caution level seas redeveloping near
shore.

Tropical Storm Milton over the far western Gulf of Mexico is
forecast to strengthen on Sunday and Monday as it moves eastward,
likely reaching hurricane intensity by early Monday morning.
Milton is forecast to continue strengthening on Tuesday and will
likely turn northeastward towards the Florida Gulf coast by
midweek. Milton will then accelerate east-northeastward across the
Florida peninsula or north central Florida on Wednesday night or
Thursday morning. Please remain updated on the latest forecasts
from the National Hurricane Center regarding Milton, as this
tropical cyclone could bring Tropical Storm or Hurricane
conditions to the northeast Florida waters.

Rip Currents: A high risk of rip currents will continue for much
of the upcoming week, with long period swells from distant
Hurricane Kirk set to arrive on Sunday afternoon or Sunday night,
creating deadly surf conditions early this week.

&&

.HYDROLOGY...
Issued at 1029 PM EDT Sat Oct 5 2024

Rivers: Major river flooding is forecast to impact the Alapaha River
near the gauge at Statenville, GA by Monday. Minor river flooding
continues all along the Altamaha River basin. Lower portions of
the Satilla River are forecast to rise to minor flooding near the
gauge at Atkinson by Monday night. As flood waters travel down
the Suwannee River, backwater flooding has begun along the lower Santa
Fe River near the gauge at Three Rivers Estates, where water
levels may reach a moderate flood towards next weekend.

Tidal Flooding: The combination of persistent onshore flow and the
approach of the annual high Spring Tides mid-month will continue
to elevate local water level departures for tidal locations this
weekend and next week. Minor flooding is expected within the St.
Johns River basin around times of high tide, especially for
locations south of downtown Jacksonville. A coastal flood
advisory remains in effect for the St. Johns River basin from
downtown Jacksonville southward. Tides will becoming further
trapped with increasing water levels this upcoming week, with the
greater tidal flooding impacts from downtown Jacksonville
southward through Putnam County to Lake George. Stronger onshore
flow early in the upcoming week will likely raise tidal flooding
levels further, with levels dependent on the northeast flow and
the eventual track and intensity of Milton.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  70  79  64  84 /  30  30   0   0
SSI  72  80  73  82 /  60  50  20  10
JAX  73  80  71  83 /  70  70  40  30
SGJ  73  81  72  82 /  70  70  50  50
GNV  72  78  70  81 /  40  60  20  30
OCF  73  81  72  82 /  20  60  30  40

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Coastal Flood Advisory until 8 PM EDT Sunday for FLZ033-038-132-
     137-325.

     High Rip Current Risk through Sunday evening for FLZ124-125-133-
     138.

GA...High Rip Current Risk through Sunday evening for GAZ154-166.

AM...None.
&&

$$