193
FXUS62 KCHS 021725
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1225 PM EST Sun Nov 2 2025

.SYNOPSIS...
A coastal trough will reside offshore today, before lifting
north and into the area this evening and tonight. High pressure
will return Tuesday and prevail thereafter.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: Surface high pressure from yesterday has since moved
northeast of the region as a potent upper level low approaches
from the northwest. An upper level jet streak has also continued
to increase in speed with the core of the jet approaching 165
kt south of Nova Scotia. At 500 mb, a closed low was hand
analyzed near the Ohio River Valley with the core of the DCVA
over eastern Tennessee and western Georgia. Out in front of the
mid-level low, a coastal trough has pushed inland with
stratocumulus also advecting inland across coastal South
Carolina. There are some weak showers that have formed well
offshore, with some movement onshore across the TriCounty
possible late this afternoon. Overall though, little in the way
of precipitation is expected today with high temperatures in the
upper 60s to near 70 degrees.

Tonight: The mid-level low will be moving east across Georgia and
then South Carolina. This cutoff low actually originated from the
northern jet stream, with the 1.5 PV surface actually being forecast
at a height of around 500/ 600 mb. This tropopause depression has
been well forecast for several days now, and usually in this type of
setup/ tropospheric folding the fractured frontal zone causes a
slight decrease in static stability with increased winds (especially
on the back side of the associated cold front). The latest forecast
soundings show the tropopause depressed to around 600 mb with most
of the profile below 600 mb saturated, but still pockets of dry air
in place. Further south towards Savannah, even more dry air is
present. As such, the general idea is for low ceilings to be present
out ahead of the upper level low and approaching cold front
(greatest risk towards South Carolina). Since the low is moving
overhead at night, a rather impressive low level inversion is
forecast so not much in the way of winds are forecast. Given the
pockets of dry air in the forecast soundings, precipitation will
likely be in the form of a weak shower or even drizzle (further
supported by low level warm air advection). The associated cold
front will then cross the zones Monday morning with a weak line of
showers possible along the front. Behind the cold front, winds turn
from the northwest and will increase in speed with gusts 15 to 20 kt
possible.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
Monday will begin with a closed mid-level low situated over the
southeastern states, while surface low pressure develops off the NC
coastline. Some isolated showers may be ongoing at daybreak, but
will quickly wane as the better forcing/moisture is located to the
northeast of the region. High pressure will begin to build into the
the region behind the departing surface low, with NW winds gusting
to around 15 mph. Given the NW flow and some cloud cover
temperatures will be cooler, with highs in the mid to upper 60s.
Overnight lows on Monday will dip into the low to mid 40s inland
with upper 40s to low 50s along the coastal counties.

Zonal flow will develop aloft Tuesday and Wednesday, while surface
high pressure builds in from the west. A dry forecast has been
maintained, with highs warming from the upper 60s/low 70s on Tuesday
to mid/upper 70s on Wednesday. Tuesday night will feature favorable
radiational cooling conditions, with lows forecast to dip into the
upper 30s inland and 40s elsewhere.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A shortwave trough will ripple across the zonal flow aloft late this
week, while at the surface a weak front will push through the
region. Moisture is not impressive with the front and the forecast
has remained rain-free. High pressure will then prevail into the
weekend. Temperatures will be slightly above normal through the
period.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Today: Stratocumulus continues to advect over the Charleston TAF
sites this morning with only a few clouds towards Savannah. A few
isolated showers exist over the waters this morning with a slow
movement onshore expected this afternoon. Abundant dry air remains
in place though (especially in the mid-levels of the atmosphere),
with a slow saturation in the low levels forecast. VFR through
today.

Tonight: VFR conditions will quickly fall towards MVFR then IFR this
evening as low level moisture advects across the terminals. This
will foster an expanding and lowering stratus deck. An upper level
low and associated surface cold front will approach the terminals
early Monday morning. Ahead of the front, widespread stratus appears
likely (especially towards KJZI and KCHS). Towards KSAV, the threat
for stratus is lower and the boundary layer is less saturated with
the best moisture advection being across KCHS/ KJZI. There is a
potential for some drizzle overnight, as there appears to be
sufficient dry air in the mid-levels (coupled with low level WAA) to
keep hydrometeors rather small. As the front crosses the terminals,
IFR cigs will quickly rise to VFR with winds backing from the
northwest.

Extended Aviation Outlook: Flight restrictions could linger into
Monday morning, with prevailing VFR thereafter.

&&

.MARINE...
Today and Tonight: Winds and seas will remain below Small Craft
Advisory criteria through the period. Northeast winds around 10
kt will slowly back to the north and then from the northwest.
Wind gusts 10 to 15 kt with seas 2 to 4 ft.

Monday through Friday: High pressure will build into the local
waters from the west Monday and into Tuesday as a surface low
pressure system develops off the NC coastline and pushes towards the
NE. This pattern will yield a pinched pressure gradient, with the
local waters located between the building high pressure and surface
low pressure. Gusty NE winds are in the forecast, possibly
approaching 25 knots, especially over the nearshore Charleston
County waters and the 20 to 60 nm offshore GA waters. Additionally,
seas could reach 5 to maybe 6 ft across these waters. A Small Craft
Advisory may be required. The center of high pressure will slowly
progress towards the local waters through the week, resulting in
winds and seas remaining well below advisory criteria through the
end of the week.

&&

.TIDES/COASTAL FLOODING...
Elevated tide cycles are expected this week due to the upcoming
full moon and perigee. Coastal flooding will be possible with
the morning high tides along the entire southeast South Carolina
and Georgia coast, especially as we head towards the middle of
the week when base astronomical levels are already at or near
minor flooding thresholds. Coastal Flood Advisories will be
likely. However, there is still considerable uncertainty with
how high the tides will reach since levels will greatly depend
on the wind direction. Most models, including the national
blended solution, are largely showing more northerly, even
somewhat north- northwest/offshore winds, through at least
Thursday. These wind directions would be less conducive to
pushing tide levels much higher than the base astronomical
levels. We will continue to monitor the latest model trends.

&&

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

&&

$$

NEAR TERM...Haines
SHORT TERM...CPM
LONG TERM...CPM
AVIATION...CPM/Haines
MARINE...CPM/Haines