890
FXUS62 KCHS 090049
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
749 PM EST Mon Dec 8 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 south through the area over
the weekend.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A surface low will continue to develop north of the region and
offshore under a stronger shortwave, with surface high pressure
building behind it. This will result in a dry conditions locally,
with a heightened surface pressure gradient resulting in slightly
breezy conditions along the coast where gusts into the teens are
expected to continue into the overnight period. Ahead of surface
high pressure, cooler air is expected to advect south into the
region while stratus begins to erode due to a substantial amount of
dry air aloft. The setup is likely to lead to noticeably colder
temps than the previous night, with overnight lows generally in the
upper 20s/lower 30s inland to lower/middle 30s near the coast.
These temps combined with breezy coastal winds could produce
wind chills into the low-upper 20s, lowest in the Tri-County Area.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
The Tuesday through Thursday period will offer much improved
conditions compared to the rainy and foggy weather that has been
observed for the past several days. A broad west to northwest flow
will dominate aloft as a large area of high pressure pressure
gradually shifts offshore of the Southeast U.S. coast. A broad
trough is forecast to dig across the eastern CONUS Wednesday into
Thursday which will help drive a weak cold front offshore Thursday
night. Moisture return ahead of the front looks meager at best with
a dir airmass progged to hold over much of the Gulf. PWATs are
forecast to surge somewhat right ahead of the front itself, but will
remain well below the 1" mark. This lack of moisture coupled with
the corridor of great quasi-geostrophic forcing progged to remain
displaced well to the north, suggests the front will pass through
dry with little prospects for measurable rainfall. Temperatures will
moderate ahead of the front with highs reaching the upper 40s/lower
50s Tuesday and lower-mid 60s Wednesday into Thursday. Lows
Wednesday morning will drop into the upper 20s well inland to the
lower 40s at the beaches with upper 30s/lower 40s inland with upper
40s/near 50 at the beaches Thursday morning.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Quiet weather will generally prevail into the weekend as high
pressure slides east across the Southeast U.S. and eventually
offshore. A cold front is forecast to backdoor in from the north on
Sunday as as the beginnings of a cold air damming/wedge take shape.
There are considerable timing differences noted with the southward
moving wedge front Sunday. The timing of the front will closely tied
to any possible surface cyclone that develops along the front. For
now, both the GFS and ECMWF ensembles, including any AI
counterparts, keep any surface low weak and tracking well to the
north. The area may be fully wedged in on Monday with cloudy and
cool conditions prevailing. There was no reason to deviate from the
08/13z NBM at this time given the uncertainty, although NBM-based
temperatures Sunday and Monday may end up being too warm depending
on how the wedge evolves.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
MVFR cigs will prevail at CHS/JZI terminals this evening and
overnight, primarily through about 13Z Tuesday. A brief window for
IFR cigs is possible at CHS/JZI terminals overnight as well, but
guidance has trended higher and dry air filtering into the region
from the west should eventually erode cloud cover near or shortly
after daybreak Tuesday. VFR conditions are then expected at CHS/JZI
terminals through 00Z Wednesday. At SAV, MVFR cigs should prevail for
the next few hours, but clouds begin to erode earlier, thus have
indicated a transition to TEMPO MVFR cigs between 01Z-03Z tonight.
There is a risk for MVFR cigs to temporarily impact the SAV later
tonight, but confidence remains too low to include in the latest TAF
issuance. VFR conditions should prevail at SAV during the second
half of the night through 00Z Wednesday.

Extended Aviation Outlook: There are no high confidence
concerns.

&&

.MARINE...
Tonight: Northerly winds gusting up to 15-20 kt early evening will
strengthen further overnight into early morning hours, resulting in
gusts around 25 kt, highest in the nearshore waters from South
Santee down to Edisto Beach, SC, and in the outer Georgia waters
from Savannah to Altamaha Sound. Seas will also build to 4-6 ft,
largest across the outer reaches of the nearshore waters from South
Santee down to Edisto Beach, SC and across the outer Georgia waters
from Savannah to Altamaha Sound tonight. Small Craft Advisories will
therefore remain in effect for these marine zones (AMZ350 and
AMZ374) through the night.

Tuesday through Saturday: Winds and seas will diminish below
advisory levels across the South Santee-Edisto Beach nearshore and
Georgia offshore waters by mid-morning Tuesday. Otherwise, winds
will turn more southerly for Wednesday and more westerly Thursday
into Saturday as high pressure slides offshore and a cold front
pushes offshore. Winds and seas could surge to Small Craft Advisory
levels Wednesday night/Thursday morning immediately ahead and just
behind the cold front. Advisories at the most likely over the South
Santee-Edisto Beach and the Georgia offshore legs where the latest
LREF probs for gusts >25 kt is running 50-80%. Otherwise, winds and
seas will remain below Small Craft Advisory thresholds.

&&

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

&&

$$

NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...