090
FXUS62 KCHS 091734
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1234 PM EST Tue Dec 9 2025

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

&&

.NEAR TERM /THROUGH TONIGHT/...
This Afternoon: Satellite shows widespread and persistent
stratus that has been in place for the past several days is
finally showing signs of thinning with distinct breaks noted
across parts of the interior. Clouds will continue to scatter
out through the remainder of the afternoon hours as low-level
moisture thins with time; however, it may very well take until
late afternoon for some areas to see considerable breaks to
develop.

Tonight: High pressure centered over Eastern North Carolina
will slowly propagate south/southeast through the night while
maintaining its influence on the area. The boundary layer should
decouple quickly around sunset with winds going calm and skies
going clear. The combination of clear skies and light/calm winds
will support strong radiational cooling. The 09/13z NBM was
used for the basis for overnight lows and range from the upper
20s well inland to the lower 40s at the beaches. These may be a
bit too warm in some of the more sheltered spots well inland,
over the Francis Marion National Forest and parts of the lower
South Carolina coastal corridor away from the beaches and I-526
corridor. These areas tend to run colder than guidance,
including the NBM, in strong radiational regimes. Unfortunately,
no local adjustments were made to account for these cooler
conditions given national policy constraints.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
After a chilly start to the day, a surface low pressure to the
north will swing the winds around to become out of the southwest
Wednesday morning, out ahead of an approaching cold front. With
near normal 850mb temperatures, Wednesday will feel notably
warmer with most areas in the lower to mid 60s. Unfortunately
mixing down these warmer temperatures does require breezier
winds, with gusts into the lower to upper 20s expected, though
at least dry conditions will prevail. Overnight lows into
Thursday will be warmer as well, upper 30s inland to mid 40s
along the coast.

Lake Winds: Wednesday afternoon into the early Thursday morning
hours, southeast winds will become sustained in the 18-22 kt
range with gusts in the 22-27 kt range. As this is expected to
create hazardous conditions, a Lake Wind Advisory has been
issued.

Thursday will see a quick moving dry cold front slip through
the region during the morning hours, with surface high pressure
building in behind it. With cold air advection and the
heightened surface pressure gradient, winds will remain on the
breezier side. Temperatures behind the front will be a few
degrees cooler than Wednesday, largely in the mid to upper 50s.
As the center of the surface high slides by to our south,
radiational cooling will aid in bringing overnight lows into
Friday back down into the lower 30s inland and lower 40s along
the coast. As the high slides out to sea, southwesterly winds
will again bring near-normal temperatures back to the region,
with highs mostly in the lower to mid 60s.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
Friday night through Saturday look to be rather uneventful, as
broad troughing aloft moves across the area and surface high
pressure remains near the region. Highs on Saturday actually
look to be above normal, with temperatures in the mid 60s to
lower 70s. It is looking like these warm temperatures continue
into Sunday, as models continue to delay a strong cold front
heading towards the area, with current consensus being the front
moving through overnight into Monday.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
09/18z TAF Discussion:
KCHS/KJZI/KSAV: Satellite shows widespread stratus is starting
to thin with breaks developing west of the terminals. These
breaks will gradually expand to all three sites later this
afternoon. Timing is still somewhat uncertain when exactly
clouds will scatter out to VFR, but 19-21z,is favored at KCHS
and KJZI with 21-23z at KSAV. Once VFR returns it will remain
VFR through 18z Wednesday.

Extended Aviation Outlook: VFR conditions expected. Breezy
southwest winds are expected Wednesday afternoon, gusting up to
25 knots.

&&

.MARINE...
Through Tonight: There are no concerns. North winds will
gradually diminish through the afternoon and evening, becoming
north to northwest 5-10 kt overnight. Seas will subside to 2-3
ft nearshore waters and 3-4 ft over the Georgia offshore waters.

Wednesday through Thursday: Out ahead of an approaching cold
front, Small Craft Advisory (SCA) conditions expected to develop
across all nearshore and offshore waters late Wednesday
afternoon into Thursday morning, not including the Charleston
Harbor. Winds will be westerly in the morning and fairly light
before swinging around to the southeast and becoming sustained
in the 20-30 kt range with gusts of 25-34 kt starting Wednesday
afternoon. Seas of 4-7 ft are also expected, lowest along the
coast and increasing heading out to sea. As the cold front
passes through Thursday morning, SCA conditions improve though
gusts into the teens continue with winds out of the west-
northwest.

Friday through Sunday: With surface high pressure across the
region, no marine concerns are expected.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...Lake Wind Advisory from 1 PM Wednesday to 4 AM EST Thursday
     for SCZ045.
MARINE...Small Craft Advisory from 1 PM Wednesday to 7 AM EST Thursday
     for AMZ350-352.
     Small Craft Advisory from 4 PM Wednesday to 4 AM EST Thursday
     for AMZ354.
     Small Craft Advisory from 4 PM Wednesday to 7 AM EST Thursday
     for AMZ374.

&&

$$