Area Forecast Discussion
Issued by NWS Charleston, SC

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790
FXUS62 KCHS 230222
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1022 PM EDT Thu May 22 2025

.SYNOPSIS...
A weak cold front will push offshore tonight, followed by
building high pressure through Saturday. A warm front will then
lift north through the area Sunday, bringing daily rain chances
back to the forecast as we head into the new week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
A cold front is forecast to slowly slide across the region
tonight. The 0Z KCHS sounding observed a deep layer of dry air
above the sfc, PW values around .9 inch. The dry air should keep
the sky clear to mostly clear tonight with no rainfall. Given
the clear sky, light WNW winds, and dry air, low temperatures
are forecast to range from the low 60s inland to the mid to
upper 60s along the coast.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
Largely quiet conditions are expected to prevail heading into
the holiday weekend as sfc high pressure strengthens. As alluded
to in the previous discussion, will see a narrow band of mid-
level vorticity graze the region Friday morning. While a few
CAMs hint that isolated showers may occur, latest soundings
would suggest that overall precipitation will be minimal as a
decent amount of dry air resides in the lower levels. Thus,
given the lack of forcing in place, have opted to remove any
mentionable PoPs with the latest forecast package. Think the
better chances will remain across central South Carolina.
Otherwise, the next best chance (30-50%) for seeing
precipitation looks to occur Sunday afternoon as a warm front
lifts northward across the region. Severe weather is not
anticipated at this time.

In regard to temperatures, Friday and Saturday will be cooler
in the wake of a reinforcing cold front with highs in the low to
mid 80s, although areas closer to the Altamaha River will peak
in the upper 80s to around 90 degrees. With the aid of southerly
flow and WAA, will see highs warm even further Sunday, with
temperatures ranging from the mid 80s to lower 90s.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
The aforementioned warm front will lift north Sunday night into
Monday night ahead of a developing system to the west. Rain
chances will increase early next week as the warm front meanders
near the area and the atmosphere becomes increasingly conducive
for a more summer-like convective pattern. Then an associated
cold front is progged to sweep across the area Tuesday night
into Wednesday, bringing another potential round of convection.
Temperatures will return to near or slightly above normal early
next week prior to the midweek FROPA.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
VFR conditions expected at KCHS, KJZI, and KSAV through 0z
Saturday. Gusty west winds should come to an end by 1Z this
evening, light winds veering from the NW tonight following the
passage of a cold front. A sea breeze may develop Friday
afternoon, resulting in winds shifting from the WSW, gusting to
15 to 20 kts at KCHS and KJZI.

Extended Aviation Outlook: Isolated showers and thunderstorms
could impact the terminals Sunday.

&&

.MARINE...
Tonight: Winds should peak in the evening, with up to 15-20
knots possible mainly in the Charleston County waters. Then by
the late night hours winds will start to turn more northwesterly
with speeds mostly in the 10-15 knot range. Seas should average
2-3 feet, with up to 4 feet possible in the outer waters.

Friday through Monday: There are no major concerns through the
period. Offshore winds will prevail Friday with northerly winds
developing early Saturday as high pressure builds from the west.
South/southeasterly winds quickly return Sunday into Tuesday as
a warm front lifts northward.

Rip Currents: Risks for rip currents in Savannah were
borderline Moderate for Saturday. Given it`s a holiday weekend,
have opted to fully nudge the risk into the Moderate Category.

&&

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

&&

$$

NEAR TERM...BSH/NED
SHORT TERM...SST
LONG TERM...SST
AVIATION...NED
MARINE...BSH/SST