Summerville, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

721
FXUS62 KCHS 231753
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1253 PM EST Tue Dec 23 2025

.SYNOPSIS...
High pressure will prevail through the holiday week. A cold
front could move through the area Sunday night or early Monday.

&&

.NEAR TERM /THROUGH TONIGHT/...
The Charleston Doppler (KCLX) radar has detected a band of light
returns moving east across portions of inland SC Lowcountry. Sfc
based observations have indicated some sprinkle activity with the
greater reflectivity. The forecast will mention sprinkles across the
inland SC Lowcountry through early this afternoon.

Tonight, the sfc pattern will feature high pressure centered over
the Deep South as a trough remains over the east facing slopes of
the southern Appalachians. This pattern should support light west
winds across the forecast during the overnight hours. A backdoor
cold front will push slow southward across NC late tonight, but will
remain north of the forecast area. Low temperatures are forecast to
range around 50 degrees.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
Overview: Warm conditions with above normal temperatures expected
through the period.

An anomalously strong mid and upper level ridge is expected to
remain west of the region through the period. At the surface, a
ridge of high pressure will be off the Mid Atlantic coast on
Wednesday, then shifting eastward on Thursday as a weak upper level
disturbance moves well north of the region. This upper level feature
seems to drag a weak surface front toward the area later Thursday
and into Friday, likely stalling and weakening over the northern
part of the area. There is some moisture return with this weak
front, but given a lack of upper level support, no significant
precipitation chances are expected.

Temperatures will be the main story for this period. Highs each day
generally in the 70s, warmest over our GA zones. Lows mostly in the
50s. These values are 10 to 15 degrees above seasonal normal
values.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Through Sunday: The strong mid and upper level ridge seems to hang
on west and southwest of the area, including much of the southern
U.S. states. This will maintain above normal temperatures through
this period, with highs in the 70s and lows mainly in the 50s.
Again, these values are 10-15 degrees above normal levels.

Sunday night and Monday: Global models and blended solutions point
toward a potential pattern shift back to colder conditions as a deep
upper level trough develops over south central Canada, and then
extending into the eastern U.S. region. An arctic surface front may
approach the region from the northwest Sunday night, then possibly
sweep through the entire region Monday. Current indications are that
this front will be pretty dry as it moves through. Cooler
temperatures expected for Monday, with highs in the lower 60s, which
are closer to normal. We will be monitoring the forecast for the
potential for very cold/subfreezing conditions again just beyond the
period Monday night and Tuesday.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
18Z TAFs: VFR. Winds should remain from the west between 5 to 10
kts tonight, turning from the northwest after sunrise Wednesday
morning.

Wednesday through Sunday: VFR conditions are expected to
prevail.

&&

.MARINE...
Tonight, winds will remain from the west around 10 kts within 20 NM,
10 to 15 kts beyond 20 NM. By late tonight, seas should subside to 2
to 4 ft.

No highlights are expected through Sunday. Winds generally 15 knots
or less and seas 2 to 4 feet, highest beyond 20 nm offshore. Winds
may increase back into SCA levels ahead of an arctic front later
Sunday. Just beyond the forecast we will continue to watch for the
potential for an arctic cold front to move across the waters Sunday
night and into Monday, which could bring back the threat for solid
SCA conditions.

&&

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

&&

$$

NEAR TERM...NED
SHORT TERM...RFM
LONG TERM...RFM
AVIATION...NED/RFM
MARINE...NED/RFM