876
FXUS62 KCHS 070546
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1246 AM EST Sun Dec 7 2025

.SYNOPSIS...
A frontal system will maintain unsettled weather into Monday,
then cold high pressure will build in. A reinforcing cold front
will move through Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Through sunrise: The feed of deep moisture has shifted to the
south with a rather notable precipitable water gradient in place
across the forecast area. The far inland counties are down
around 0.5" while the far southern end of the GA coast is up to
around 1.25". This belt of moisture could shift a bit further
south, but will likely remain as it is for the next several
hours. Therefore, most of the forecast area will not see
additional rain, except for the area around southern Long
County, McIntosh County and coastal Liberty/Bryan. The main
forecast challenge instead is low stratus and fog which is
already ongoing across the SC Midlands. The setup is good with
wet ground from all the recent rainfall, light to calm winds,
and high clouds trying to clear out from the north. Model
guidance favors the best chance for more greater coverage and
lower visibility is inland of the coast. Dense fog is possible
and we will have to monitor the need for Dense Fog Advisories.

Today: Aloft, the pattern will continue to feature southwest
flow as a shortwave digs across the Plains and approaches the MS
Valley. At the surface, high pressure will remain the primary
feature with a front still draped off the Southeast coast,
across north FL, and across the northern Gulf. There is good
model agreement that the moisture feed and precipitation shield
to the south will gradually spread back to the north along the
GA coast through the morning. One of the main forecast questions
is how far north will the light rainfall spread. Hi-res model
consensus and the HREF favors the light precipitation getting as
far north as Hinesville, Savannah, and almost up to Beaufort
and the Charleston County coast. Additional rainfall amounts
will be light with a few hundredths to a tenth along a line from
Reidsville to Savannah and Beaufort south, then up to a quarter
of an inch across McIntosh County and portions of the GA coast.
It will be yet another very chilly and cloudy day with highs
only reaching the low 50s for most of the area.

Tonight: The shortwave will push east of the lower MS Valley
and toward the southern Appalachians. This will drive surface
low development across the northeast Gulf as well as off the
Southeast coast. Most of the rainfall will remain to the south
and southeast along the boundary and associated with the
developing surface low. However, we will see an area of light
precipitation develop more closely associated with the trough
aloft and track across MS, AL, and GA. While these showers will
mostly remain west of the forecast area through the overnight, a
few showers could get into the far western zones by around
sunrise. We will still be in an environment with plenty of low-
level moisture so low stratus will persist and we could again
see fog development. Lows are forecast to fall into the low to
mid 40s in most areas.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
Scattered showers will move through Monday morning as the
primary shortwave passes by to the northwest. Meanwhile, cool
high pressure will build from the west. Tuesday looks fairly
cool with highs in the upper 40s to lower 50s, but temps quickly
rebound on Wednesday with highs pushing into the lower 60s in
most areas.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
Temperatures will moderate late in the week, then a reinforcing
cold front sweeps through Friday. A few showers may accompany
the front, followed by much colder air.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
The 06z TAF period begins with a mix of conditions ongoing
across the area. Some observation sites are bouncing from IFR to
MVFR and even VFR. The TAF sites all are starting off MVFR, but
the thinking is that they will lower to IFR in the next hour or
two. There is fog potential, and possibly dense, though the best
chances through sunrise are expected to be inland of the TAF
sites. So we will keep ceilings as the main driver of flight
categories through sunrise. Guidance suggests that KCHS and KJZI
will improve to MVFR for much of the day before lowering back to
IFR near the end of the TAF period. At KSAV, IFR is more likely
as rain spreads back in at the terminal by the early afternoon.
For now, we think the rain will stay just south of KCHS and
KJZI. Conditions could be variable throughout the TAF period so
amendments will almost certainly be needed as conditions evolve.

Extended Aviation Outlook: IFR/MVFR ceilings expected to
persist through Monday night, then improving to VFR.

&&

.MARINE...
Today through tonight: Winds will start off northeast 5-10
knots this morning then gradually become northerly 10-15 knots
through the evening. Then overnight, winds will turn more
northwesterly 10-15 knots with gusts potentially approaching 20
knots at times. Seas should average 2-3 feet through the period.

A brief period of Small Craft Advisory winds/seas is possible
Monday night over the Charleston nearshore waters and GA
offshore waters. The next chance for advisories will be Friday
night behind a reinforcing cold front.

&&

.TIDES/COASTAL FLOODING...
Astronomical tides will remain elevated Sunday but will be on a
declining trend. Coastal Flood Advisories could be needed for
the Sunday morning high tide cycle, but the current forecast is
for Charleston to fall just shy of the minor coastal flood
threshold.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.

&&

$$

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