315
FXUS62 KCHS 100555
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1255 AM EST Wed Dec 10 2025

.SYNOPSIS...
A cold front will move through this evening and push offshore
Thursday morning with another cold front possibly moving through
late Sunday. Cold high pressure will then build in.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: Aloft, zonal flow will prevail across the region ahead
of a vigorous trough diving across the Upper Midwest and into
the TN/OH Valley. At the surface, high pressure will start the
day across the region before getting suppressed to the south as
a cold front draws closer from the northwest. The forecast
remains dry with plenty of dry air across the region. Southwest
flow ahead of the front will yield a much warmer day than the
last several, with highs getting up into the upper 50s and low
60s. The warmer temperatures will produce better mixing an
breezy southwest flow at times in the afternoon. Frequent gusts
into the 15-20 mph range are expected, which could start to tick
upward closer to sunset as the better low-level wind field
starts to press in from the west.

Tonight: The cold front will pass through after midnight and
the best low-level wind field will come through just ahead of
the front during the evening hours. The breeziest conditions are
expected to stretch across the period beginning around 8-9 pm
through about 1-2 am. During this time, frequent gusts of 15-20
mph are expected everywhere, with 20-25 mph along the coastal
corridor. With winds remaining elevated through the night, the
increased mixing will prevent temperatures from getting too
cold. Still, mid to upper 30s are advertised inland which will
range to the low 40s along the coast.

Lake Winds: Southwest winds across Lake Moultrie will gradually
turn more westerly and strengthen this evening and through the
early morning hours on Thursday. Frequent gusts into the 25-30
knot range are expected, and a Lake Wind Advisory is in effect.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
Dry high pressure will prevail through the period. There will
be a steady warming trend as the high shifts offshore and a warm
advection regime sets up. Highs in the low to mid 50s Thursday
will rise to mid/upper 60s by Saturday.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
A strong cold front will move through Sunday evening, followed
by a brief cooldown, then gradual warming. We could see a few
hours of Cold Weather Advisory wind chill (~20F) over the
northern counties Monday morning.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
As the 06z TAF period begins the forecast looks to be a bit
tricky through the next 6-8 hours. Observations across the area
show there is some patchy fog developing and satellite imagery
shows a slowly expanding area of stratus down around KSAV. The
main forecast challenge concerns what happens with this area of
stratus and whether or not it will expand over the next few
hours. Model guidance suggests that this will happen and given
there is still plenty of low-level moisture and very light
surface winds, it seems plausible. Therefore, we have initiated
KSAV with MVFR ceilings and don`t return conditions to VFR until
09z. At KCHS and KJZI, shallow ground fog is already ongoing
and we have introduced a TEMPO group to account for MVFR
ceilings roughly from 08-09z through 11-12z.

For the rest of the period, VFR conditions will prevail and the
main forecast challenge will be winds. Southwest flow will
become breezy this afternoon, with gusts as high as 15-20 knots
possible. The strongest winds are expected this evening through
the early morning hours as a cold front passes. Winds will turn
more westerly with time and gusts up to around 25 knots will be
possible.

Extended Aviation Outlook: VFR.

&&

.MARINE...
Today through tonight: Conditions across the local waters will
start off pretty quiet this morning before steadily ramping up
through the rest of the day as a cold front approaches from the
northwest. By sunset, we expect to see a solid 15-20 knots
across all waters with gusts starting to reach up to 25 knots in
the Charleston County waters. The strongest winds are then
expected from the evening through the early morning hours when
wind speeds are expected to increase into the 20-25 knot range
with frequent gusts up to around 30 knots. There will even be a
window of time from the late evening into the early morning
hours where wind gusts around gale force will be possible in the
Charleston County waters and the outer GA waters. We will
maintain the Small Craft Advisory for now, but it isn`t entirely
out of the question that a marginal Gale Warning could be
needed with future forecast updates. Also, we have expanded the
Small Craft Advisory to include Charleston Harbor for the
evening and early morning hours. Seas will ramp up with the
increasing winds, becoming 3-5 feet by early evening and then
peaking in the early morning hours as 6 ft seas get into the SC
nearshore waters and up to 7 feet in the outer GA waters. Winds
and seas will both start to diminish a bit as sunrise Thursday
approaches, but will overall conditions will continue to support
the ongoing Small Craft Advisories.

6 ft seas will continue over the offshore GA waters through
Thursday morning which necessitates a continuation of the Small
Craft Advisory.

Solid Small Craft Advisory conditions anticipated Sunday night
through Monday for most if not all waters after a cold front
sweeps through.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...Lake Wind Advisory from 6 PM this evening to 5 AM EST Thursday
     for SCZ045.
MARINE...Small Craft Advisory from 6 PM this evening to 5 AM EST
     Thursday for AMZ330-354.
     Small Craft Advisory from 3 PM this afternoon to 7 AM EST
     Thursday for AMZ350-352.
     Small Craft Advisory from 3 PM this afternoon to noon EST
     Thursday for AMZ374.

&&

$$

NEAR TERM...BSH
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...BSH/JRL
MARINE...BSH/JRL