140 
FXUS62 KJAX 120941
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
441 AM EST Sun Dec 12 2021

.NEAR TERM [Through Tonight]...

A cold front is sliding south and east through SE GA into the I-10 
corridor of NE FL early this morning with a line of showers swiftly 
moving eastward from the suwannee valley to Waycross and Brunswick.
Surface high pressure at the surface is to our southeast over the 
northern Bahamas and the southwesterly winds around 5-10 mph are 
keeping dewpoints elevated into the mid to upper 60s across the 
area. A potent mid/upper level trough over the eastern third of 
the US is lifting NE along the eastern seaboard with most of the 
shortwave energy translating north of the region into the Carolinas
and the Mid Atlantic states. Therefore, most of the activity should
remain showers through sunrise with very limited most unstable 
CAPE less than 300 J/kg still along the FL/GA state line as of the
06Z Laps analysis. Some low level Surface to 3km shear values up 
to 30 knots and a quick nose of near 70 dewpoints caused low topped
shower to produce some rotation near the intersection of I-10 and
I-75 overnight, but a steady weakening trend was observed with 
just a broken line of showers traveling along the I-10 corridor. 
Low stratus has formed ahead of the showers from Gainesville to 
the Jacksonville area to Fernandina Beach with areas of fog near 
Gainesville east to Palatka and south to and Ocala and patchy to 
areas of fog may spread eastward to St Augustine through sunrise.


Showers will slowly break down in coverage and become more isolated 
through the morning hours as the cold front slides down into the 
area with low overcast skies along and ahead of the front and 
gradual clearing behind the front this afternoon over SE GA. Patchy
to areas will lift by the late morning hours south of I-10 over 
NE FL and as the front slows it's progress and stalls over north 
central FL. Winds will veer northerly and then north northeast 
behind the front with breezy winds at the coast 10-20 mph and 
around 10 mph or less inland. Highs will be coolest over SE GA 
with mid 60s as high pressure builds to the northwest behind the 
front and then to the north late in the afternoon with warmer 
highs just behind the front in the low to mid 70s over NE FL and 
upper 70s along the front over north central FL while Jacksonville
and the I-10 corridor only reaches the upper 60s and endures 
overcast skies for a majority of the day. 

Tonight the high will build north over the Carolina piedmont while
an inverted trough forms over the NE FL coastal waters. Some showers
will develop, but mainly stay offshore as mid level shortwave 
energy streams over the east coast of FL. Winds will become 
northeasterly and remain breezy at the coast overnight with mostly
cloudy skies south of I-10 along the remnants of the cold front. 
A gradient in lows will stretch across the area with low 40s over 
inland SE GA close to the Altamaha river and mid to upper 40s 
south of Waycross to the FL/GA state line with low 50s at the GA 
coast and mid to upper 50s for much of NE FL and low 60s at the 
Flagler county coast. 

.SHORT TERM [Monday Through Tuesday]...

Monday: Zonal flow is forecast on Monday. An upper level shortwave 
will move east along the northern Gulf coast and over the area 
Monday night. At the surface, high pressure will settle over the
Carolinas, and a coastal trough will also develop. Low level 
moisture is forecast to linger across northeast Florida, and an
isolated shower is possible along the coast south of St. 
Augustine. Temperatures will be near to slightly above normal, 
with highs in the mid to upper 60s across southeast Georgia and 
the 70s across northeast Florida. Northeasterly onshore flow will
prevail, and overnight lows will be mild along the coast in the
upper 50s to lower 60s. Across the interior, lows will be in the 
upper 40s to lower 50s across southeast Georgia and the mid to
upper 50s to around 60 for northeast Florida. 

Tuesday: Flow aloft will become northwesterly to northerly as the
shortwave trough exits to the east and upper level ridging begins
to build towards the area from the southwest Gulf of Mexico. 
Northeasterly onshore flow will prevail. Temperatures will warm a
couple degrees from Monday for highs and lows. 

.LONG TERM [Wednesday Through Sunday]...

Upper level ridging will start the period across the western Gulf 
of Mexico, and then build across the area by the end of the week 
and then east of the area over the weekend.  Surface high pressure 
will stretch from Maine southward across the Carolinas on 
Wednesday and then shift east southeastward through the end of the
week to near Bermuda. East northeast low level flow on Wednesday
is forecast to become easterly on Thursday and southeasterly by
Saturday. A cold front may approach the area late Saturday into
Sunday, and have low chances for showers across the area next
Sunday. Temperatures are forecast to be well above normal through 
the weekend. 

&&

.AVIATION...
[Through 06Z Monday]

A mixture of MVFR to LIFR conditions from low ceilings are 
impacting the inland TAF sites KVQQ, KGNV, and KJAX while VFR 
conditions prevail at the coastal TAF sites farther ahead of 
incoming showers along a cold front moving southeast into the 
region tonight. Ceilings will lower and fog will increase in 
coverage from the Gulf of Mexico over the northeast florida sites
while showers roll across the duval county terminals and KSSI by 
08Z to 10Z time period with prevailing IFR to LIFR conditions 
sinking then farther south towards KSGJ. Showers will end from 
northwest to southeast, by 15Z across the duval county terminals 
with MVFR ceilings and then improving over the southern sites KGNV
and KSGJ between 18Z and 21Z to at least MVFR ceilings. Winds 
will be gusty at the coastal terminals around 11 to 13 knots with 
gusts to near 20 knots from the north during the afternoon as 
high pressure build northwest of the region behind the front with 
winds near 10 knots at the inland sites from the north. The front 
will stall just south of the regional terminals with only KSSI 
likely to see a return to VFR conditions this afternoon through 
the end of the 06Z TAF period. 

&&

.MARINE...

A cold front will move across the local waters through today. 
High pressure will strengthen north of the region tonight into 
Monday and Tuesday while a coastal trough develops offshore of 
the Atlantic coast. Onshore flow will increase late today into 
Monday with Small Craft Exercise Caution headlines in place, 
then weaken mid-week as the surface high shifts farther south and
builds offshore of the Carolina and mid Atlantic coast.

Rip Currents: Moderate risk for NE FL and SE GA beaches through 
Monday.

&&

.PRELIMINARY POINT TEMPS/POPS...

AMG  65  41  67  46  70 /  10   0   0   0   0 
SSI  65  51  66  55  69 /  10   0  10  10  10 
JAX  68  53  70  56  71 /  20  10  10  10  10 
SGJ  70  59  72  60  73 /  20  10  10  10  10 
GNV  72  56  76  57  76 /  20   0   0   0   0 
OCF  76  58  78  60  77 /  20  10   0   0   0 

&&

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