804
FXUS62 KCHS 090545
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1245 AM EST Tue Dec 9 2025

.SYNOPSIS...
High pressure will extend across the region for much of the
week. A cold front will push offshore Thursday morning with
another cold front possibly moving through late in the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: Aloft, the pattern will be broadly cyclonic as low
amplitude troughing covers the southeast and south-central
CONUS. At the surface, high pressure will start the day
stretching from New England, across the Southeast, and into the
lower MS Valley. This high pressure will then persist across the
Southeast and settle nearly right on top of the forecast area
by the end of the day. With plentiful dry air (precipitable
water values ~0.25") and no forcing, the forecast is dry. The
main change today will be the long awaited scattering any
lingering low stratus this morning followed by full sun in the
afternoon. While the return of the sun will certainly be
welcomed, it does not mean it will be a warm day. Instead low-
level thickness values support another very chilly day. Forecast
highs are for upper 40s across southeast SC and upper 40s and
low 50s for southeast GA. Such values would be on the order of
15 degrees below normal.

Tonight: With high pressure on top of the forecast area and
clear skies, we should see good radiational cooling conditions
tonight. This will yield lows solidly in the upper 20s inland,
with a transition zone from low to mid to upper 30s as you get
closer to the immediate coastline.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
Dry high pressure will prevail through the period.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
Guidance has continued to delay the passage of the strong cold
front, now showing it moving through late Sunday and maintaining
relatively warm temps over the weekend.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
The 06z TAF period begins with MVFR conditions at KCHS and KJZI
while KSAV sits in an open area with VFR conditions. Northerly
flow will help to push a large area of mostly MVFR stratus into
the area over the next few hours which should then persist
through sunrise. Model guidance suggests that ceilings could
lower into the IFR range for a few hours generally between
12-15z, mostly at KCHS and KJZI. We should finally see the
stratus scatter out and conditions return to VFR first at KSAV
in the mid to late morning hours, then at KCHS and KJZI by
midday.

Extended Aviation Outlook: VFR.

&&

.MARINE...
Today through tonight: The day will start with north-northeast
winds solidly in the 15-20 knot range, with gusts into the low
20 knot range. Wind speeds will then steadily diminish through
the day, becoming 5-10 knots by sunset for much of the local
waters. Overnight, winds will be around 5 knots out of the
northwest and becoming more westerly with time. Seas will start
off the morning in the 3-5 knot range, with a diminishing area
of up to 6 ft in the Charleston County waters and the outer GA
waters. Seas will then gradually decline through the overnight,
becoming mostly 3-4 ft by sunrise Wednesday. Lingering Small
Craft Advisory conditions for the Charleston County waters and
outer GA waters will come to an end by mid morning.

Brief Small Craft Advisory conditions expected for most waters
late Wednesday afternoon through Wednesday night.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until 10 AM EST this morning for AMZ350-
     374.

&&

$$

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