Area Forecast Discussion
Issued by NWS Charleston, SC

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445
FXUS62 KCHS 261009
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
509 AM EST Wed Nov 26 2025

.SYNOPSIS...
A strong cold front will sweep through late today, with high
pressure building into the region Thursday and into the
weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Update: An update has been sent to increase pops slightly per
latest near term guidance and radar trends. Mentionable pops
were expanded east all the way to the coast. No other changes
were made.

A cold front is on target to push from west-east across the
South Carolina Lowcountry and Southeast Georgia today, reaching
far interior Southeast Georgia by mid-morning, the I-95 corridor
by late morning and finally clearing the upper Charleston
County coast by mid-afternoon. Radar composites show a pretty
healthy area of showers/tstms with the front, being mostly
driven by forcing associated with the right entrance region of
100-110 kt jet that is strengthening along the southern flanks
of a powerful upper low that is pivoting across the Upper
Mississippi Valley. This corridor of upper forcing is expected
to steadily weaken with time as the jet streak gradually lifts
out to northeast while net moisture values and mean 850 hPa
theta-e both lower with time as drier air begins overtake the
frontal surface from the west. This will likely result in a
steadily weakening of convection along/head of the front through
the morning hours.

How much convection survives prior to the front pushing
offshore is still a bit uncertain, but most guidance support a
broken line of showers moving into the western zones later this
morning and steadily weakening as it approaches the coast.
Average QPF will range from a trace to 0.10", highest across
interior Southeast Georgia. Pops today range from 20-30%
along/west of I-95 with 10-20% between I-95 and the beaches.
Highs will warm into the mid-upper 70s except upper 60s/lower
70s with southwest winds becoming a bit breezy later this
morning and continuing until FROPA. Gusts could reach as high as
25-30 mph at times.

Cooler and drier conditions will prevail tonight as secondary
surge pushes through this evening and high pressure builds in
from the west and northwest. Lows Thanksgiving morning will
range from the upper 30s/lower 40s well inland to the upper
40s/near 50 at the beaches.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
A longwave trough aloft will dominate over the southeastern
states on Thursday before shifting off the East Coast into
Friday, yielding zonal flow into the weekend. At the surface
high pressure will build into the region from the west behind
the departing cold front. This high pressure will prevail into
the weekend, resulting in a dry forecast. The main forecast
highlight into the weekend will be the noticeably cooler
temperatures. Highs on Thursday will reach to around 60, with
Friday and Saturday struggling to get out of the 50s across most
locations. Overnight lows will similarly be cooler, with
freezing temperatures likely along and west of I-95 both
Thursday and Friday nights. Upper 30s/low 40s are expected along
the coastal counties.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
Zonal flow will dominate aloft through the remainder of the
weekend, with high pressure prevailing at the surface. This
pattern will yield a cool and dry forecast, with no rain chances
and below normal temperatures forecast.

There are indications that a coastal low could develop just off
of the southeastern coast early next week. However, there is
much uncertainty with this system, as cluster analyses are not
showing good agreement between models.

&&

.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
26/12z TAF Discussion:
KCHS/KJZI/KSAV: VFR will prevail at all three terminals through
27/12z. A cold front will reach the terminals by early afternoon
with winds shifting to the west. A line of weakening showers
just ahead of the front should large dissipate prior to reaching
the terminals. The only exception could be KSAV where a bit
more coverage is progged. VCSH was highlighted 15-18z at KSAV to
account for this. Prior to FROPA, wind gusts could reach as
high as 20-25 kt beginning mid-morning.

Extended Aviation Outlook: Prevailing VFR.

&&

.MARINE...
Through Tonight: Southwest winds will increase ahead of an
approaching cold front today. The front will reach the waters by
mid-afternoon and should push east by late afternoon. A
reinforcing surge will push offshore tonight, resulting in a
secondary wind surge to the northwest. Both surges should max
out no higher than 15 kt to perhaps 15-20 kt with gusts
generally holding less than 25 kt. Right now, it looks like
winds will not reach Small Craft Advisory levels, although it
could get close at times. Seas will peak 2-4 ft, except 3-5 ft
over the South Santee-Edisto Beach nearshore leg this afternoon
with 2-4 ft prevailing all waters overnight in the offshore
flow.

Thursday through Saturday: High pressure will build into the
region on Thursday behind a departing cold front. Post-FROPA
will see shift to the NE, with winds around 15 knots with gusts
to 20 knots. Some gusts on Thursday night could approach 25
knots, especially over the 20 to 60 nm offshore GA waters.
However, the duration of time of these conditions is too short
to warrant a Small Craft Advisory. Seas are forecast to average
2 to 3 ft with some 4 ft seas in the 20 to 60 nm offshore GA
waters.

&&

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

&&

$$