Sparr, Florida Weather Forecast Discussion

594
FXUS62 KJAX 060545
AFDJAX
Area Forecast Discussion
National Weather Service Jacksonville FL
145 AM EDT Sat Sep 6 2025
...New NEAR TERM, SHORT TERM, LONG TERM, AVIATION, MARINE, HYDROLOGY...
.NEAR TERM...Today and Tonight...
Calming conditions, mostly clear skies, and shrinking dewpoint
depressions may result in areas of patchy shallow fog across inland
areas this morning, which may become locally dense in areas near
marsh/estuaries around sunrise.
Onshore flow will continue locally as a stalled trough to the
south begins to lift northward into central FL today. Meanwhile,
rising heights aloft will trend temperatures warmer by another
degree or two this afternoon, putting highs in the low 90s inland
and upper 80s along the coast. WIth the seasonable dewpoints and
low 90s temperature readings, peak heat index values will rise to
the lower 100s across NE FL this afternoon.
As the aforementioned trough or pseudo warm front approaches,
moisture aloft will accompany it and aid the development of numerous
showers and scattered thunderstorms generally south of I-10 this
afternoon. Interactions with the St Johns River and Lake George
breezes may initiate convection as early noon today. Isolated
thunderstorms are generally expected along and south of a
moisture/instability gradient that will extend from Jacksonville
to Gainesville. Main concerns will be locally gust winds,
lightning, and localized minor flooding/ponding due to sluggish
storm motion.
The aforementioned warm front will continue to lift north tonight
and rest across NE FL by dawn Sunday. Patchy to areas of fog are
expected with some of those areas becoming dense in areas between
the Interstate 10 and 95 corridors. Tonight`s lows will be right
around normal with inland lows in the lower 70s and mid/upper 70s
along the coast.
&&
.SHORT TERM...
(Sunday through Monday night)
Issued at 1254 AM EDT Sat Sep 6 2025
Sunday, A broad mid/upper trough will shift from the upper Midwest
into the eastern Great Lakes and OH/TN valley. This will push a
surface cold front into the Gulf coast and SE GA. As the surface
trough to the south dissipates and the new front moves in, deep
moisture levels will rise with PWATs increasing to 1.8-2.10 inches
across NE FL while near normal over SE GA 1.5-1.8 inches. The
additional moisture, lift along the front and inland progressing
Atlantic seabreeze and slightly steeper lapse rates aloft (~6.0
c/km) will support increased chances for showers and T`storms with
numerous showers and T`storms over NE FL south of a line from
Gainesville to St Augustine and scattered coverage of showers and
T`storms northward into SE GA as the front moves in. Locations
west of US 441 may see diminished chances as the front pushes
through and entrains drier air in it`s wake. Slightly stronger
0-6km shear in the environment ahead of the front may support a
higher threat for wind gusts 40-55 mph and small hail in stronger
T`storms. East northeasterly winds will continue, highest along
the coast 10-15 mph and diminishing to 5-10 mph west of I-95.
Highs will rise into the low 90s inland to the upper 80s along the
coast. Max heat index values will rise to around 100-105 from
Jacksonville south and west into central FL.
Sunday night, the front will press into NE FL with isolated showers
lingering past midnight over inland NE FL, but revamping along the
coast towards sunrise as coastal convergence increases over the
waters. Light easterly winds 5-10 mph will back north northeasterly
and increase to 10-15 mph at the coast in the predawn morning hours.
Lows will be in the mid 70s at the coast, low 70s over inland NE FL
and around 70 over inland SE GA.
Monday, the broad trough to the north will lift northeastward into
New England/eastern Quebec on Monday as a ridge axis moves east
from the plains into the mid and upper MS river valley. Under the
ridging, surface high pressure will sprawl across the Midwest
states and move into the upper OH valley near the end of the day.
As the high moves east, NNE winds will become more northeasterly
and increase as an inverted coastal trough forms near the
Gulf stream as the front stalls from central FL into the offshore
FL waters. This feature will create strong coastal convergence
sending waves of showers and embedded T`storms onshore pushing
inland south and westward into the St Johns river basin and north
central FL. Only far NW portions of SE GA will see diminished
chances for showers due to drier continental air flow from the
northeast well inland. Heavier convergent bands may produce
locally heavy rainfall amounts from the coast into the St Johns
river basin. Abundant clouds and showers will keep our high
temperatures below average in the mid 80s along the coast and into
I-95 with upper 80s west of I-95 and near 90 degrees along and
west of I-75 where more partly cloudy skies reside.
Monday night, the surge of northeasterly winds will continue a
fetch of coastal showers moving onto the immediate coast with
coverage diminishing with inland extent. Locally heavy rainfall
threat will continue east of the St Johns river to the coast with
a few T`storms as well. Lows will be in the upper 60s over inland
SE GA but moderate to the mid 70s along the coast. NE winds will
continue elevated at the coast 10-20 mph and 5-10 mph inland.
&&
.LONG TERM...
(Tuesday through Friday)
Issued at 1254 AM EDT Sat Sep 6 2025
High pressure to the north building eastward will wedge a cooler
and drier air down the lee of the Appalachians while inverted
troughing persists near the Gulf stream waters along the
previously stalled frontal boundary. This will continue an
unsettled pattern for much of the area as mid/upper troughing
forming over the spine of the appalachian mountains sends a parade
of shortwaves moving across the area that will add lift and spin
to the atmosphere over the top of breezy surface NNE onshore
flow. This will support persistent coastal convergence over the
first coast with numerous to widespread showers and embedded
T`storms along the NE FL coast inland to I-75 which will allow for
locally heavy rainfall amounts where the bands move onshore,
continuing inland to I-75. Per the long range Grand Ensemble
(includes the European, Canadian, and American Ensemble models) in
DESI, The probability of locations receiving 2 inches of rain or
more next week is up to 30% from the JAX beaches into the St
Johns river and Ocala with up to 50% over coastal Flagler county.
Breezy conditions will prevail through much of the week as the high
to the north shifts more to the northeast with a pinched gradient
leading to northeasterly winds at the beaches 15-20 mph with higher
gusts to 30 mph and 10-15 mph inland. The expectation during this
long duration onshore flow event is for a stretch of dangerous
rip currents at the beaches, elevated surf (4-6 ft breakers), and
beach erosion impacting the beaches until the gradient relaxes
late in the week as the high weakens to the northeast as another
cold front arrives from the northwest next Friday.
Temperatures during the period will be feature below normal highs
in the low to mid 80s at the coast and mid to upper 80s inland
with near to below normal lows in the mid to upper 60s over inland
SE GA/Suwannee valley and the low 70s along the coast.
&&
.AVIATION...(06Z TAFS) Issued at 1254 AM EDT Sat Sep 6 2025
As a stream of cirrus shifts east, patchy low stratus will
develop at inland airfields along and north of the I-10 corridor
around 09z and then expand eastward toward the I-95 around
sunrise. Occasionally IFR ceilings are possible at KJAX and KVQQ
between 10-13z. There will be increasing shower chances south of
I-10 today with best chances for thunderstorm impacts at KGNV
between 20z-24z. Otherwise, an easterly flow increasing to 8-12
knots will be predominant at all airfields. After sunset, winds
will begin to calm with more widespread low stratus development
likely between 06-12z. There is an increasing potential of fog
across NE FL Sunday morning, which could become locally dense.
&&
.MARINE...
Onshore flow pattern continues as a weak warm front lifts north
and stalls across the northeast Florida and coastal waters through
tonight. A cold front will approach from the north as the stalled
warm front morphs into a coastal trough on Sunday, increasing
rain and thunderstorm chances over the waters. By Monday, the cold
front reach the Georgia waters and send a surge of northeasterly
winds southward down the coast. A period of small craft advisory
conditions are possible Monday and Tuesday with gradually
weakening northeasterly winds Wednesday onward. The front will
continue toward south Florida through the week with a reinforcing
front pushing towards the local waters by next weekend.
Rip Currents: Moderate risk of rip currents is expected with
breakers around 2-3 ft. A cold front and northeasterly wind surge
will elevate surf and increase rip current risk along the SE GA by
Monday.
&&
.HYDROLOGY...
Elevated tides due to higher astronomical tides will combine with
a prolonged period of northeasterly flow next week and
potentially bring another Minor coastal flood event, particularly
south of Jacksonville within the St Johns River as well along the
Atlantic coast, at times of high tide.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG  93  70  92  69 /   0   0  20  20
SSI  87  74  88  74 /   0  10  30  30
JAX  91  73  92  74 /  20  10  40  20
SGJ  89  75  89  75 /  30  20  50  30
GNV  94  72  93  72 /  40  10  40  20
OCF  91  73  91  73 /  50  20  50  20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&
$$

NWS JAX Office Area Forecast Discussion