634
FXUS62 KCHS 081343
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
843 AM EST Sat Nov 8 2025

.SYNOPSIS...
High pressure will extend across the region through the
weekend. A strong cold front will cross the region by Sunday
night bringing much colder conditions to the area next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
UPDATE: KCLX shows showers breaking out south of I-16 this
morning with weak warm air advection/isentropic ascent ongoing.
Activity should increase a bit later this afternoon ahead of a
850-700 hPa shortwave that is currently propagating across the
Deep South. Modified RAP soundings yield moderate levels of
instability with SBCAPE 1500-2000 J/kg with in a moderately
sheared environment featuring 0-6km bulk shear values around 40
kt. Although mid-level lapse rates will remain fairly muted, a
few strong tstms can not be ruled out later this morning and
especially this afternoon as surface temperatures rise and low-
level lapse rates increase. Gusty winds and small hail are the
most likely hazards. The risk for tstms reaching severe levels
remains low given the less than ideal mid-level lapse rates.
Near term pops were adjusted slightly to reflect current radar
and short term model trends.


Out ahead of an approaching cold front, weak positive theta-e
advection in the mid-levels is resulting in scattered to broken
cloud coverage, with winds remaining just mixy enough to keep
overnight lows in the mid 50s inland into the lower 60s along
the coast. Along the cold front, scattered to areas of showers
and isolated thunderstorms are occurring, though model consensus
remains on the lower end of what exactly the rainfall coverage
will look like as the front stalls to our northwest. Despite the
weak positive theta-e advection continuing along with some
instability, the NBM only gave slight chances for the
showers/storms to continue into the late morning hours,
primarily for far southeast Georgia. Convection allowing models
would suggest the probabilities for rain would extend into
portions of southeast South Carolina as well, so given the
similar environment continuing did extend the coverage of
showers in both space and time much further north into South
Carolina.

While we`ll likely see a break in rain coverage, convection
allowing models have noticeably increased the chances for
showers and isolated thunderstorms throughout the morning and
into the afternoon hours. This is due to continued modest lift
from the positive theta-e advection, decent instability of
750-1500 J/kg, high shear of up to 50 knots, and k-index values
in the mid-30s. SPC noted a similar trend, and even introduced a
level 1 out of 5 (Marginal) risk for severe thunderstorms
across inland southeast South Carolina and southeast Georgia.
Given the lack of pops from the NBM, went ahead and increased
chances for showers and thunderstorms to 30% to account for the
possibility of thunderstorms, with a low probability for severe
thunderstorms. Given the warm-air advection and breezy
southwesterly winds, afternoon high temperatures still look to
peak into the lower 80s across southeast Georgia and upper 70s
in southeast South Carolina, while those along the coast will
stay in the mid 70s.

Into the early overnight hours, expect another round of light
scattered showers and isolated thunderstorms, primarily limited
to inland areas. As a strong cold front approaches from the
west- northwest, the surface pressure gradient increases, and
will keep winds on the semi-breezy side. This will also keep
temperatures on the warmer side, with overnight lows in the
lower to mid 60s, warmest along the coast.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY/...
Sunday: A deep 525DM closed low will dive across the Great
Lakes region through the day. The longwave trough will extend
south to the Gulf, with the axis remaining to the west. At the
sfc, a deepening low pressure system will track across the Ohio
River Valley during the morning, reaching PA/NY by the
afternoon. A strong cold front will sweep across the Southeast
U.S. during the daylight hours, timed to reach SE GA and SC
Lowcountry during the late afternoon to early evening hours. The
late arrival of the front should allow high temperatures to
range around 80 across the SC Lowcountry to the low 80s across
SE GA. Forecast soundings indicate a significant inversion will
remain around h75 through much of the day. However, by the late
afternoon, the inversion should weaken as the cold front
approaches from the west, CAPE values may range between 500-800
J/kg. Shear should increase along and ahead of the cold front,
with 6km bulk shear reaching around 55 kts by sunset. ML/AI
guidance indicates that the region may see the potential for
15-30 percent of severe weather with 25 nm of any given point.
SPC current highlights the region with a marginal risk for
severe thunderstorms.

The cold front will push offshore late Sunday evening, with
strong CAA expected across the forecast area through the rest of
the night. In fact, NAM12 indicates that H85 temps fall below
0C for portions of inland GA and SC. Low temperatures Monday
morning are forecast to range from the upper 30s across inland
GA to the mid 40s along the coast.

On Monday, GFS indicates that 12Z H85 temps along a line from
KSAV to KCHS will range around 4C. H85 temperatures should fall
through the day, falling to around -4C by sunset. Temperatures
will struggle to warm with the ongoing strong CAA, despite the
full sun. High temperatures should remain around 15 degrees
below normal, highs generally in the mid 50s. The surge of CAA
may lead to gusty winds across the region, possibly reaching
Lake Wind Advisory criteria during the late afternoon.

Monday night, the H5 trough should ripple over across the
forecast area during the overnight hours. The center of 1030 mb
high should remain over Deep South, maintaining a 2 mb pressure
gradient. The combination of lingering cold llvl thicknesses and
clear sky should allow temperatures to steady cool through the
night. Using a blend of guidance, low temperatures are forecast
to range in the 20s along and west of I-95, values in the low
30s to the east. Only areas along the immediate coast area
forecast to remain above freezing by daybreak Tuesday morning.
These temperatures will challenge record low values, see Climate
section below. In addition, wind speeds should generally remain
between 5 to 10 mph, yielding wind chill values in the low to
mid 20s, some pockets in the upper teens are possible. The
forecast hard freeze should end the growing season for the
majority of the forecast area. There is also a chance that a
Cold Weather Advisory could be needed for a few areas.

Tuesday, the center of high pressure sourced from central
Canada will push over the forecast area. High temperatures are
forecast to remain around 20 degrees below normal, generally in
the low to mid 50s. In fact, we could see a new record low max
at KCHS, see Climate section below. In addition, dewpoints may
favor values in the teens across SE GA to around 20 across the
SC Lowcountry during the afternoon. Afternoon RH values may fall
into the low to mid 20s across SE GA to around 30 percent
across the Lowcountry. Fortunately, the weak pressure gradient
should keep wind speeds between 5 to 10 mph.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
Tuesday night, clear sky with light to calm winds should
provide strong radiational cooling conditions through the night.
Low temperatures should fall to around 30 degrees along and
west of I- 95, with mid to upper 30s to the east.

Temperatures should trend warmer through the rest of the work
week. In fact, temperatures should return to mid November
normals by Thursday, remaining near normal through the rest of
the forecast period. Conditions should remain dry under dry NW
mid-level flow.

&&

.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
08/12z: VFR through the day at all TAF sites. Areas in inland
southeast Georgia may see some MVFR cigs throughout the morning
hours, but not expected to reach the SAV terminal. Isolated to
scattered showers and thunderstorms may form later this morning
into the afternoon hours, have included PROB30s at SAV and CHS
as they are not expected to be prevailing at this time. Late
overnight into Sunday, an MVFR to IFR stratus deck may be
pushing into the region from eastern Georgia.

Extended Aviation Outlook: Prevailing VFR into the weekend.
Isolated showers or thunderstorms could impact the terminals on
Sunday afternoon, possibly bringing brief flight restrictions.
Gusty NW winds around 20 knots will develop Monday, diminishing
into Tuesday.

&&

.MARINE...
Through Tonight: Winds will become more uniformly southerly
later this afternoon into tonight as high pressure shifts
farther offshore and a cold front approaches from the west and
northwest. Speeds will generally remain 10 kt or less, but will
increase closer to 10-15 kt as daybreak approaches. Seas will
average 4 ft or less through the overnight hours.

Sunday through Wednesday: A strong cold front will approach the
marine zones on Sunday. Return flow ahead of the front should
yield southwest winds between 10 to 15 kts, some gusts to 20 kts
possible. Seas are forecast to range between 2 to 4 ft. A
strong cold front will sweep across the region Sunday night into
Monday. In the wake of the front, winds should turn from the
northwest and strengthen to 20 to 25 kts, with gusts near 30
kts. Seas will build Sunday night through Monday, reach 3 to 5
ft across the nearshore with 6 ft seas across the outer GA
waters.

Monday night, a surge of CAA will push across the Atlantic
waters. Northwest winds may increase above 25 kts with gusts
into the low 30s across the Atlantic waters. Speeds appear close
to Gale force Monday evening outside the CHS Harbor, with Small
Craft conditions across the harbor. Seas should peak Monday
night, ranging between 4 to 8 ft. Small Craft Advisories are
likely for all waters, with a Gale Watch/Warning not out of the
question for a portion of the waters. Conditions should improve
on Tuesday and Wednesday as high pressure settles over the area.

&&

.CLIMATE...
Upcoming Record Low Temperatures:

November 11 (Tuesday):
KCHS: 29/1943
KCXM: 32/1913
KSAV: 31/1968

November 12 (Wednesday):
KCHS: 27/1943
KCXM: 33/1894
KSAV: 30/2011

Upcoming Record Low Maximum Temperatures:

November 10 (Monday):
KCHS: 46/1991
KCXM: 47/1991
KSAV: 49/1968

November 11 (Tuesday):
KCHS: 54/1968
KCXM: 46/1913
KSAV: 49/1913

&&

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

&&

$$