North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

205
FXUS62 KCHS 230655
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
255 AM EDT Fri Oct 23 2026

.WHAT HAS CHANGED...
Key Message 1 and 2 and all other sections were updated. Key
Message 3 added.

&&

.KEY MESSAGES...
- 1) Dry conditions and below normal temperatures will continue
  into early next week.

- 2) Multi-day coastal flooding event expected this weekend
  into next week.

- 3) Strong northeast flow this weekend and into early next
  week will result in several coastal hazards including rip
  currents, high surf, and beach erosion.

&&

.DISCUSSION...
KEY MESSAGE 1: Dry conditions and below normal temperatures
will continue into early next week.

Through Daybreak: Conditions early this morning are the same as
the past several. Clear skies, calm winds within a decoupled
boundary layer and a resident dry airmass are promoting strong
radiational cooling. Hourly temperatures are running a few
degrees colder than the 23/01z NBM, which is not surprising
given its classic warm bias in strong radiational regimes. Lows
were adjusted down from the NBM given current trends and are on
track to bottom out in the lower-mid 40s inland to the upper 50s
at the beaches. The pressure gradient is forecast to slightly
tighten as daybreak approaches which should curtail the
radiative processes in some areas, especially east of I-95.

Today and Tonight: There is no change in the surface pattern
with strong high pressure prevailing. High temperatures today
will run just a bit cooler than Thursday with temperatures aloft
forecast to cool slightly as a strong shortwave drops south
along the Southeast U.S. coast. Even with the cooler
temperatures aloft, full insolation is expected with highs
poised to warm into the lower-mid 70s away from the beaches. The
pressure gradient will begin to quickly tighten tonight as low
pressure begins to organize east of the Southern Bahamas and
strong high pressure centered over New England steadily wedges
south across the Carolinas and Georgia. This will result in a
uptick in winds through the night with breezy conditions
developing at the beaches and around the Santee-Cooper lakes.
Despite clear skies, it will be an overall warmer night with
lows ranging from the upper 40/lower 50s inland to around 60 at
the beaches. Some mid 40s could occur, mainly in the Jenkins-
Allendale corridor where winds will be the lightest.

Saturday through Thursday: Surface high pressure will extend
across the region through late week. Over the weekend, the high
will strengthen inland while a coastal trough develops offshore.
The air mass will remain quite dry. The pattern will support a
rain-free forecast through at least early next week. Despite
plenty of sunshine, temperatures will lean on the cooler side of
normal. Highs will top out in the lower to mid 70s for the
weekend and early next week. Low temperatures will fall into the
40s across many interior locations.


KEY MESSAGE 2: Multi-day coastal flooding event expected this
weekend into next week.

Astronomical tides will continue to rise through the weekend
and into next week with the upcoming lunar perigee (10/28) and
full moon (10/26). With another period of strong northeast flow
on the way this weekend into next week, large tidal departures
will start to overlap with increasing astronomical tides,
providing increased probabilities of seeing a multi-day coastal
flooding event for the entire coast.

Today, minor coastal flooding is likely in the Charleston
Harbor with the morning high tide, currently forecast to reach
around 7.0 ft MLLW, where a Coastal Flood Advisory is in effect.
Another round of minor flooding is possible with this evening`s
high tide before conditions deteriorate further heading into the
weekend. Tides should remain below minor flood thresholds at
Fort Pulaski for both tides.

Over the weekend and into the middle of week, the potential for
coastal flooding escalates to moderate-to-major levels at
Charleston Harbor and minor-to-moderate levels at Fort Pulaski.
While the morning high tide will be the dominant peak each day,
water levels possibly pushed more than a foot above predicted
levels could cause coastal flooding during evening high tides as
well. Persistent onshore winds will also prevent water from
fully draining during low tide, creating extended periods of
elevated water and prolonged inundation. This setup aligns with
the highest astronomical tides of 2026 as we approach the full
moon on October 26 and lunar perigee on October 28. Astro tides
will peak Tuesday and Wednesday at 6.87 ft MLLW in Charleston
Harbor and 8.90 ft MLLW at Fort Pulaski before accounting for
wind-driven surge. There is an increasing possibility that tides
could approach major flood stage at Fort Pulaski Monday morning
and trends are being monitored for forecast adjustments.


KEY MESSAGE 3: Strong northeast flow this weekend and into early
next week will result in several coastal hazards including rip
currents, high surf, and beach erosion.

Rip Currents: Strong northeast winds and increased wave action
will support an elevated rip current risk over the weekend and
into early next week. A Moderate Risk for rip currents is in
place for all beaches today, followed by a High Risk Saturday.
An enhanced period of rip currents will likely continue into
early next week.

High Surf: Breaking wave heights of 5 ft or higher will be
possible and High Surf Advisories could be needed this weekend
into early next week. The combination of elevated tides,
increased wave action, and persistent gusty northeast winds will
likely produce beach erosion, with the most significant erosion
occurring around high tide cycles this weekend.

Lake Winds: Gusty northeast winds will pick up across Lake
Moultrie Friday night and persist through the weekend. Winds
could briefly gust around 25 kt early Saturday morning, but due
to the short duration, a Lake Wind Advisory will be withheld
for Friday night. Gusts will then decrease by late morning as
the boundary layer decouples over the relatively cooler lake
waters. After sunset Saturday, the pattern flips and winds will
rapidly pick up as cold air advection occurs over the warmer
lake waters. This will trigger strong mixing, dragging 30 kt
wind gusts down to the lake surface. A Lake Wind Advisory will
likely be needed starting Saturday night. The combination of
steady northeast winds and 2-3 ft waves could yield lakeshore
erosion along the southwest side of the lake along with some
overwash. This is includes areas from roughly Pinopolis to
Blacks Camp near Cross.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
23/06z TAFs:
KCHS/KJZI/KSAV: VFR through 24/06z.

Extended Aviation Outlook: Breezy northerly winds anticipated
through Monday morning. Gusts could reach 25-30 kt, especially
during the afternoon hours Saturday and Sunday.

&&

.MARINE...
Today: It will remain relatively quiet across the waters today
before conditions deteriorate tonight. Northeast winds will
begin to increase to 15-20 kt later this morning and persist
into the afternoon in response to a tightening of the pressure
gradient. Seas across the Georgia offshore waters have finally
dropped below 6 ft and the Small Craft Advisory there was
cancelled early. Seas will average 2-4 ft nearshore waters and
4-5 ft offshore waters.

Tonight: Conditions will begin to steadily deteriorate tonight
as the pressure gradient between high pressure over New England
wedging south and low pressure developing east of the Southern
Bahamas steadily tightens. Northeast winds are expected to
increase to 20-25 kt with gusts to 30 kt and 25-30 kt with gusts
to 35 kt over the offshore waters. Seas will build to 4-6
nearshore and 6-8 ft offshore. A Small Craft Advisory has been
posted for all nearshore waters and Charleston Harbor for
tonight with a Gale Watch over the offshore waters. A Gale
Warning would normally be issued at this time given the onset of
frequent gale-force gusts is within 24 hours, but there are
some slight timing uncertainties of when these gusts will
occur. A Gale Watch was favored over a Gale Warning given this.

Saturday and Sunday: A deepening high pressure wedge to the
north will result in deteriorating conditions over the local
waters this weekend. Winds will reach their peak Saturday and
Sunday evening with solid gale-force conditions across the
coastal waters. Prolonged northeast fetch will yield dangerous
seas which look to peak Sunday evening at 8-12 ft across the
nearshore waters (0-20 nm) and 11-15 ft across the offshore
waters (20-60 nm).

Monday through Wednesday: Winds and seas will gradually trend
lower Monday afternoon, but at the least, Small Craft Advisory
level conditions could persist across local waters outside the
Charleston Harbor through the period. Gale conditions could
linger over the offshore waters through the entire period as
well due to a persistent, tight pressure gradient anchored
across the region.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...Coastal Flood Advisory from 5 AM to 8 AM EDT this morning for
     SCZ149-150.
MARINE...Small Craft Advisory from 2 AM Saturday to 6 AM EDT Monday for
     AMZ340.
     Small Craft Advisory from 6 PM this evening to 6 AM EDT
     Saturday for AMZ360-362-364.
     Gale Watch from Saturday morning through late Sunday night for
     AMZ360-362-364.
     Gale Watch from this evening through late Monday night for
     AMZ380-382-384.

&&

$$