Hardeeville, South Carolina Weather Forecast Discussion

003
FXUS62 KCHS 201810
AFDCHS
Area Forecast Discussion
National Weather Service Charleston SC
210 PM EDT Sat Sep 20 2025
.SYNOPSIS...
High pressure will prevail through early next week. A coastal
trough could form near the coast during the middle of next
week, then a cold front will approach from the west late in the
week.
&&
.NEAR TERM /THROUGH TONIGHT/...
The mid-levels will consist of a weak trough just to our
northeast. Though, larger scale troughing should prevail over
the Southeast U.S. At the surface late this afternoon, weak
High pressure will be inland. Temperatures peaking in the upper
80s to lower 90s are generating some instability, aided by dew
points in the 60s. The deterministic models and most of the CAMs
have isolated to maybe scattered convection into this evening.
Though, the NBM continues to be much drier than the models.
Either way, any convection will quickly dissipate around sunset,
with it being dry overnight. The overnight surface pattern will
consist of High pressure moving over New England. This will
push a cold front south and across our area, with it moving
through our northernmost counties late tonight, likely making it
to the SC/GA border by daybreak Sunday. Behind the front, winds
will shift to the northeast and increase. Expect slightly
cooler low temperatures, with the mid 60s far inland and upper
60s to lower 70s along the immediate coast.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
Weak surface high pressure will remain northeast of the area
Sunday into Monday. The upper ridge extending from the western
Atlantic into the eastern United States will gradually shift
east during this period, allowing the 0-6 km flow to become SSE.
Moisture will gradually increase over the area with clouds
increasing Sunday night into Monday. Greater moisture across
coastal southeast GA could support isolated sea breeze
convection Monday afternoon. A weak coastal trough could develop
on Tuesday, though the best forcing will remain offshore. Temps
will continue to be near or slightly above normal.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
A closed upper low is forecast to move toward the Southeast mid
to late next week. Surface low pressure and a cold front could
affect the area Friday or Saturday, though guidance continues to
be quite inconsistent on details. Decent rain chances could
begin as early as Thursday.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
18Z TAFs: Radar indicates isolated convection developing across
our area this afternoon. It`s expected to persist until sunset,
then quickly dissipate. The probabilities of direct impacts to
our TAF sites are too low to warrant mention in the TAFs. Late
tonight, MOS and the ensembles hint at some shallow radiational
fog just before sunrise. Since these probabilities are low, we
kept mention of this out of the TAFs. So VFR should prevail for
the entire TAF time period.
Extended Aviation Forecast: Mainly VFR.
&&
.MARINE...
Through Tonight: Onshore winds early will turn to the NE this
evening, then remain sustained 10-15 kt overnight. Winds should
be the strongest at daybreak Sunday, which is when wind gusts
could hit 20 kt, mainly further offshore. Seas should average
2-4 ft.
Sunday through Monday, a wedge of high pressure will build
inland as a trough of lower pressure forms over the Atlantic
waters. This will result in northeast winds of 15-20 knots, with
some gusts near 25 knots possible. Seas generally 3 to 5 feet.
At this time, still expect conditions to remain below SCA
levels.
Tuesday and Wednesday, the wedge of inland high pressure
weakens and moves eastward, with low level winds decreasing and
veering to more east and southeast. Winds generally 15 knots or
less and seas 2 to 4 feet through this period.
Rip Currents: There remains a Moderate Risk of rip currents
along our Georgia beaches into this evening. Moderate Risk
Sunday and Monday due to stronger than normal NE winds and
moderate swells.
&&
.TIDES/COASTAL FLOODING...
Strong northeasterly winds are expected to create larger tidal
departures this weekend, which could result in tide levels
approaching 7 ft MLLW (minor) in Charleston Harbor starting with
this evening`s high tide cycle. The risk for minor coastal
flooding should continue into early next week. Coastal Flood
Advisories could eventually be needed for minor saltwater
flooding in Charleston and Coastal Colleton Counties.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.
&&
$$
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...

NWS CHS Office Area Forecast Discussion