341
FXUS62 KCHS 201249
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
849 AM EDT Sun Apr 20 2025

.SYNOPSIS...
High pressure will linger across the region into Tuesday. A
front will approach the region by midweek then become
stationary over or near the area through late week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
No major changes were made for the mid-morning update. Winds may
not be quite a gusty within the sea breeze circulation compared
to the past few afternoons, but there will still be a
noticeable increase with its passage, especially over the
coastal counties. Highs were nudged down into the mid 70s for
the Waterfront Park/Downtown Charleston observation site and
raised slightly into the upper 80s for a few spots over interior
Southeast Georgia. The rest of the forecast is on track.

Subtropical upper-level ridge remains draped across the southeast
CONUS and Florida Peninsula along with a large expanse of surface
high pressure that extends from the southeast states into the
Atlantic. Pattern will change very little over the next few days
maintaining our stretch of dry weather and warm temperatures. A
fair amount of high cloud cover along the western edge of the
upper ridge will continue to cycle through the southeast region
through tonight leading to overall partly sunny/partly cloudy
conditions through the period. High temperatures today will
reach the lower to middle 80s most areas...cooler along the
coastal corridor. Lows tonight will range from the upper 50s to
lower 60s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
Deep layered ridging will persist over the Southeast U.S. coast
through Tuesday. Strong subsidence will be prevalent as noted in
model soundings via an 850mb capping inversion. Dry conditions are
forecast Monday and Tuesday with warming temperatures. Despite rain-
free weather, partly to mostly cloudy skies are forecast with thick
cirrus moving in overhead Monday. As for high temperatures, on
Monday low to mid 80s will be common everywhere except the beaches
where it will stay in the mid/upper 70s. Tuesday will be a few
degrees warmer with highs peaking in the mid to upper 80s, and
possibly 90 degrees in isolated spots.

A cold front will approach from the northwest Tuesday night, slowly
sagging into the forecast area and then stalling near the South
Carolina Midlands Wednesday. A few showers and thunderstorms are
possible near the boundary, enhanced by the afternoon sea breeze.
POPs were lowered to around 20-35% as models show a slightly more
north stalled position. Convection will be focused across the
southeast South Carolina interior; however, this location will
greatly depend on the placement of the stalled front. High
temperatures should peak in the upper 80s to low 90s away from the
coast. Low temperatures will stay in the low/mid 60s both Monday and
Tuesday night.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Wednesday night into Thursday, the aforementioned stationary front
could meander somewhat but should remain within or the near the
forecast area. Similar conditions are expected Thursday with a few
showers/t-storms developing inland resulting from boundary/sea
breeze interactions. By Friday, the front will retreat north,
decreasing rain chances. Also, the upper ridge will break down and
ripping weak shortwaves as well as a nearby passing weak surface low
could bring a few showers and perhaps a thunderstorm over the
weekend. Above normal temperatures will persist through the
weekend.

&&

.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
12Z TAFS: A touch of shallow ground fog is possible early this
morning at the terminals. Otherwise, some heating of the day Cu
will be found across the region today while scattered to broken
high cloud cover will persist across the region through tonight.

Light/calm winds early will modestly increase through the
morning and into the afternoon along with a sea breeze push this
afternoon.

Extended Aviation Outlook: Gusty winds are possible each
afternoon at all terminals with the passage of the sea breeze.
There are no other concerns.

&&

.MARINE...
Winds were increased to 15 kt with gusts to 20 kt in the
Charleston Habor with the sea breeze. The rest of the forecast
is on track.

Through Tonight: Southerly flow will persist across the coastal
waters through tonight with speeds around 10 knots and seas 2-4
feet.

Monday through Friday: High pressure will prevail in the Atlantic
through Tuesday, yielding benign conditions and southerly flow,
shifting southeasterly Thursday. Expect higher winds near the coast
and across the Charleston Harbor with the afternoon sea breeze. Seas
will average 1-3 ft.

&&

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

&&

$$