Port Royal, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

747
FXUS62 KCHS 232353
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
653 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 /UNTIL 6 AM WEDNESDAY MORNING/...
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 /6 AM WEDNESDAY MORNING 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 /00Z WEDNESDAY THROUGH SUNDAY/...
24/00z TAF Discussion:
KCHS/KJZI/KSAV: VFR through 25/00z.

Extended Aviation Outlook: 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.

Friday Through Sunday: 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.

&&

$$