North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

379
FXUS62 KCHS 240722
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
322 AM EDT Thu Sep 24 2026

.WHAT HAS CHANGED...
All Key Messages and sections were updated.

&&

.KEY MESSAGES...
- 1) Breezy and cooler weather will persist into the weekend.

- 2) The coastal flood risk ramps up due to persistent northeast
  winds and high astronomical tides.

- 3) High Risk for dangerous rip currents today due to strong
  offshore swell, with an elevated risk continuing through the
  weekend.

&&

.DISCUSSION...
KEY MESSAGE 1: Breezy and cooler weather will persist into the
weekend.

Thursday: Rather impressive cold air damming (CAD) for early
Fall has developed a firm grip on the sensible weather the next
24 hours with today being the peak of the wedge. Looking a loft,
the parent upper trough will begin to eject over the Mid-
Atlantic this morning and into the afternoon. Strong surface
cyclogenesis has begun off the Carolina coast as the beginnings
of a stout early season nor-easter begins. The surface pressure
gradient is expected to tighten throughout the day today as the
surface low strengthens. Surface north-easterlies shall
increase with frequent gusts across the area around 25 to 30 mph
especially along the coast. While this is not enough to warrant
any wind products, conditions could be a little treacherous
across area bridges this afternoon and caution is advised. Along
with the breezy coniditons, the upper trough moving overhead
will support light isentropic upglide over top the cold wedge.
This typically results in widespread cloud cover and usually
light drizzle/precipitation as warm moist air rises overtop the
colder air and cools. Given cooler air within the wedge is
firmly in place, plus the combination of poor solar insolation
and some diabatic cooling with precip the expectations are for
high temperatures to be stuck on the cooler side this
afternoon. This is certainly a welcome change from brutal heat
that the region has experienced for most of the summer. As is
typical for CAD events, blended guidance has struggled with high
temperatures and typically underdoes the isentropic ascent. As
a result, we went rather aggressive in keeping temperatures on
the cooler side of guidance with highs inland likely barely
reaching 70 degrees and low 70s along most of the coast.
Depending on how much drizzle occurs; this may not be enough and
much like yesterday high temperatures could even struggle to
get into the upper 60s for most of the area. So if you`re
planning to head out do not expect the warm side.


Friday into Sunday: By Friday, the upper trough and adjacent
nor-easter shall lift off into the northeast and towards the
northern Atlantic eroding the wedge in the process. While the
wedge may be gone, the cold air will not be as stiff northerly
winds behind the trough shall usher in a rather stout punch of
continental polar air. Conditions should dry out rather quickly
on Friday and Saturday with clouds clearing and temperatures
dropping. Highs on Friday and Saturday will be warmer given the
drier column and plenty of sunshine to support heating but
overnight lows will be noticeably cooler with temperatures in
the 50s except for the immediate coastline. This will be our
first real shot of Fall!

KEY MESSAGE 2: The coastal flood risk ramps up due to persistent
northeast winds and high astronomical tides.

Breezy northeasterly flow combined with the upcoming full moon
(9/26) will yield an increase in tidal departures across the region.
Coastal flooding impacts will ramp up today as each of the next
three consecutive high tides starting this evening (Thursday
evening, Friday morning, and Friday evening) has the potential to
reach moderate flood stage along the Charleston and Colleton County
coastlines. Coastal Flood Advisories will likely be needed during
each high tide cycle. An extended period of coastal flooding impacts
could be seen during each high tide cycle through early next week.

Further south along the lower South Carolina and southeast Georgia
coasts, this evening`s high tide has the potential to reach minor
flood stage (around 9.5 ft MLLW). A Coastal Flood Advisory could be
needed. Additionally, latest guidance continues to target peaks near
the minor flood threshold for the Friday morning and evening high
tides.

KEY MESSAGE 3: High Risk for dangerous rip currents today due to
strong offshore swell, with an elevated risk continuing through the
weekend.

Strengthening low pressure well off the Carolina coast will support
breezy winds, building surf, and 7-8 second swells today. This setup
will drive a High Risk for rip currents along the entire South
Carolina and Georgia coastline. On Friday, the surf will transition
to a longer-period swell (12 seconds at 3-4 ft), resulting in a
Moderate Risk for all area beaches. An elevated rip current risk
will persist into the weekend as long-period swell lingers.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
0Z TAFs: MVFR ceilings are expected to continue through the
overnight and potentially lower to IFR by early morning.
Northerly winds around 10 knots shall persist becoming gusty
this afternoon with gusts to around 20 to 25 knots possible.
Weak lift developing late this morning and into the afternoon
may allow for IFR ceilings to persist throughout the day. In
addition to the lowered ceilings, rounds of drizzle to light
showers may develop within the area of lift, significant
reductions in visibility are not anticipated. Ceilings may reach
MVFR by late Thursday afternoon as the showers and precip relax.
Winds should relax overnight as clouds slowly clear.

Extended Aviation Outlook: Gusty winds will persist into
Thursday, possibly Friday.

&&

.MARINE...
Thursday: Strong northeasterly flow will persist throughout the
day today with likely Gale conditions beginning over the
offshore waters this morning. Winds across all the marine zones
will range from around 20 knots nearshore to 25 to 30 knots
well offshore with gusts well offshore nearing 40 knots. Seas
will quickly increase to around 5 to 9 feet nearshore and 9 to
11 feet well offshore. These conditions are expected to
continue through Thursday night.

Friday and Saturday: Winds and seas will gradually subside Friday
into Saturday as the inland wedge weakens and the offshore low moves
northeast away from the area. Northerly wind gusts are expected to
drop below 25 kt on Friday, though seas will be slower to diminish.
Small Craft Advisories will likely be needed through Saturday night,
mainly for 6 ft seas lingering across the outer Georgia waters.

Sunday through Tuesday: Marine conditions will continue to improve
Sunday as the pressure gradient weakens under broad surface high
pressure. No headlines are anticipated, with southerly winds 10 kt
or less and seas subsiding to 2-3 ft.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...High Risk for Rip Currents from 8 AM EDT this morning through this
     evening for GAZ217-219-239-241.
SC...High Risk for Rip Currents from 8 AM EDT this morning through this
     evening for SCZ148>151.
MARINE...Small Craft Advisory from 6 AM this morning to 11 PM EDT this
     evening for AMZ340.
     Small Craft Advisory until 8 PM EDT Friday for AMZ360-362.
     Small Craft Advisory until 8 AM EDT Saturday for AMZ364.
     Gale Warning from 6 AM this morning to 6 AM EDT Friday for
     AMZ380-382.
     Small Craft Advisory until 2 PM EDT this afternoon for AMZ384.
     Gale Warning from 2 PM this afternoon to 6 AM EDT Friday for
     AMZ384.

&&

$$

Black/BRS