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000 
FXUS62 KJAX 110124
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
824 PM EST Tue Dec 10 2019


.NEAR TERM [Through Tonight]...Cold front just nw of area will
move across se Ga this evening and across ne Fl after midnight.
Low clouds and patchy fog off the Gulf will spread ne across
mainly ne Fl ahead of the cold front. Scattered showers will 
accompany the frontal passage. The front will be south of the area
by morning with lows in the mid 50s over se Ga and upper 50s/lower
60s across ne Fl.

.AVIATION...[Through 00Z Thursday]
Current VFR conditions will lower to IFR-LIFR as low cigs and 
vsbys move in ahead of approaching cold front. Behind the front 
winds will shift to the nw between 06z-10z and increase Wednesday
morning. Gradual improvement to MVFR conditions expected Wednesday
morning.

&&

.PREV DISCUSSION [409 PM EST]...

.SHORT TERM [Wednesday Through Friday]...

Front will push south of the region Wednesday with little chance
of any precip in the morning, as most of the energy from shortwave
is not located close to the CWA. Still likely to see overrunning
clouds Wednesday with some sprinkles possible as what's left from
shortwave trough passes through the area. Temps will be much
cooler than today's upper 70s and lower 80s, with highs only 
upper 50s to around 60 over the northwest zones, mid 60s around
I-10 area, and lower 70s possible over the far srn zones. Breezy
north-northeast winds mainly around coastal counties near 20 mph
and gusty. Wed night, sfc high pressure pushes east to be due 
north of the area bringing sfc flow to the northeast, with the 
cold front slowing down as it pushes southward down the FL 
peninsula. Northeast flow may bring some chance for a few showers 
for the southeast zones, with breezy flow continuing for coastal 
counties up to 20-25 mph at times. Lows are colder as coolest air 
arrives with lows in the 40s and 50s, coldest over interior 
southeast GA. 

Thursday, more changes occurring as the front stays to our south,
and another shortwave moves into the south central U.S. helping 
to enhance lift and cloudiness across the northern Gulf, and north
FL and srn GA. Winds will be continuing out of the northeast with
chance of showers expected. Breezy north-northeast winds expected
again near 20 mph. Rain chances ramp up late Thursday-Thursday 
night and Friday as the shortwave moves through the lower MS 
valley and the southeast states and induces sfc low cyclogenesis 
over the northern Gulf of Mexico. The low will push northeast and 
will be north of the area late Friday night. Ahead the low 
pressure, warm front is likely to push into northeast FL which 
should enhance rainfall chances. A few strong storms possible 
Friday afternoon and evening as the low passes through the region 
and low level winds increase.


.LONG TERM [Saturday Through Tuesday]...

Sfc low pressure will likely be north of the area with a trailing cold
front to push south of the area Saturday, and weak high pressure 
will gradually build into the area Saturday night through Sunday. 
Gradual clearing skies Saturday through Sunday with near seasonable
temperatures. Weak high pressure moves east of the area Monday 
and resultant warm front will push northward through the area 
Monday. Temps warm Monday to above normal. A cold front is forecast
to approach the area Monday night with a chance of precip again 
Tuesday as the front makes its way into the deep south, with 
frontal passage either as early as early Tuesday morning or 
Tuesday night, given the timing disagreement between GFS and 
ECMWF.


.AVIATION...
[Through 18Z Wednesday]

VFR conditions will prevail through the remaining daylight hours,
but another round of IFR-LIFR cigs and vsbys is anticipated late
tonight/early Wed morning ahead of an approaching cold front.
Behind the front Wed morning, winds will pick up from the 
northwest, blowing out low vsbys, but those low cigs may be 
stubborn to lift even at the end of the TAF cycle.


.MARINE...

South to southwest flow continues into this evening ahead of an 
approaching cold front. The cold front is forecast to push into 
the GA waters around 06z and then into northeast FL waters 06-12z 
Wed. Cold front should be south of the waters 15z Wed. Small Craft
Advisory conditions (20-33 kt and seas 7 ft) will be possible 
starting around as 14z-18z. Some gale force wind gusts are likely 
and due to lower confidence on gale warning have elected to have 
SCA at this time. Pressure gradient remains pinched Wed night 
through Thu night between the front to our south, which becomes 
stalled over srn FL, and high pressure ridge to our north. 
Pressure gradient becomes loose Friday as trough develops offshore
of northeast FL and wedge of high pressure gives way to a 
developing low pressure system moving through the northeast Gulf 
of Mexico. As the low tracks northeastward across the southeast 
late Friday night into Saturday, winds may shift around to the 
south, but forecast is highly dependent on the eventual track of 
the low. It does appear winds will come around the northwest 
sometime on Saturday as the low pressure moves away and trailing 
cold front from the sfc low moves through the area. Weak high 
pressure builds into Sat night to Sun likely resulting in winds 
and seas on the low side.

Rip Currents: Moderate risk of rip currents at northeast Florida 
and southeast Georgia beaches rest of today and possible high 
risk of rip currents on Wednesday.

Coastal impacts: We will see elevated water levels Wed night 
through Thursday evening due to increased northeast flow (and
higher surf) and the astronomical full moon phase Thu, Dec 12th. 
Model extratropical surge fcst suggesting about 1 foot, and for 
now no coastal advy is anticipated but will be monitored.


.HYDROLOGY...
At this time, rainfall forecast amounts with the stronger system 
Thursday night into Friday night week range from a low of only 
0.5 inches over coastal northeast FL to 1.5 inches over parts of 
southeast GA.

&&

.PRELIMINARY POINT TEMPS/POPS...

AMG  53  62  44  60  49 /  30  10  10  20  60 
SSI  56  63  50  62  56 /  30  10  10  30  60 
JAX  59  68  52  65  58 /  30  10  10  40  60 
SGJ  62  69  56  69  61 /  40  20  20  40  50 
GNV  61  71  54  68  59 /  30  10  10  20  40 
OCF  62  75  55  72  60 /  30  20  10  20  30 

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...Small Craft Advisory from 10 AM Wednesday to 9 AM EST Friday for 
     Waters from Altamaha Sound GA to Fernandina Beach FL from 
     20 to 60 NM-Waters from Fernandina Beach to St. Augustine 
     FL from 20 to 60 NM-Waters from St. Augustine to Flagler 
     Beach FL from 20 to 60 NM.

     Small Craft Advisory from noon Wednesday to 5 AM EST Friday for 
     Coastal waters from Altamaha Sound to Fernandina Beach FL 
     out 20 NM-Coastal waters from Fernandina Beach to St. 

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