North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

964
FXUS62 KCHS 181048
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
648 AM EDT Sun Oct 18 2026

.WHAT HAS CHANGED...
The Aviation section was updated for the 12z TAFs.

&&

.KEY MESSAGES...
- 1) Below normal temperatures and gusty winds will continue as
  a powerful nor`easter meanders offshore of the North Carolina
  Outer Banks and Mid-Atlantic States.

- 2) The risk for high surf and dangerous rip currents will
  persist into early this week.

&&

.DISCUSSION...
KEY MESSAGE 1: Below normal temperatures and gusty winds will
continue as a powerful nor`easter meanders offshore of the North
Carolina Outer Banks and Mid-Atlantic States.

This Morning: Early morning surface analysis and satellite data
show broad high pressure centered over the Central Appalachians
extending south into the Southeast U.S. with cyclogenesis
ongoing about 250 miles southeast of Cape Hatteras. The
pressure gradient between these two features is keeping breezy
conditions in place with gusts 30-35 mph common at the beaches.
Lows this morning are on track to bottom out in the mid-upper
40s inland with lower 50s at the beaches. With breezy conditions
holding, downright chilly conditions will occur with wind
chills expected to drop into the upper 30s to mid 40s away from
the immediate coast as daybreak approaches.

Today and Tonight: The synoptic reasoning has not changed. A
nor`easter off the Outer Banks will steadily deepen through
tonight as it becomes more vertically aligned with an upper low
that is forecast to develop near the North Carolina coast. The
system will move little for the next 24-hours or so as it
becomes detached from the main belt of the westerlies while broad
high pressure builds deeper into the Southeast States. This
will keep breezy conditions in place for one more day with clear
skies prevailing. Despite full insolation, temperatures will
remain well below normal for mid-October with afternoon highs
only expected to reach the mid-upper 60s. Clear skies and rain-
free conditions will persist into tonight with lows dropping
into the mid-upper 40s inland with mid-upper 50s at the beaches,
warmest along the Georgia coast where the low- level flow
relative to the of the coastline advect a slightly more modified
airmass from off the warmer Atlantic.

Lake Winds: Elevated north/northeast winds will persist across
Lake Moultrie through early Monday morning. Winds of 20-25 kt
with gusts to 30 kt this morning are expected to drop to 15-20
kt with gusts to 25 kt later this afternoon and finally below
Lake Wind Advisory criteria during the early morning hours
Monday. Waves 2-3 ft will subside to 1-2 ft this afternoon and
evening. The risk for some minor lakeshore erosion and overwash
remains, mainly along the south side of the lake including
Pinopolis, Lions Beach and Short Stay.

Monday through Saturday: A nor`easter will be located off well
off the coast of NC Monday morning. Meanwhile, strong High
pressure will be located over the Northeast, with it`s periphery
stretching down into the Southeast U.S. The nor`easter will
very slowly shift away from our region through mid and late this
week. Though, the periphery of High pressure will persist
across the Southeast U.S. possibly weakening its grip. As it
does this, dry conditions will prevail and high temperatures
will increase. Based on MOS, 850 mb temperatures, and low-level
thickness values, high temperatures should be in the upper 60s
to lower 70s on Monday under sunny skies. They`re expected to
rise into the mid to maybe upper 70s Tuesday, again with sunny
skies. The 70s will generally persist Wednesday through the end
of the week, which is within a few degrees of normal. However,
the dry conditions will cause low temperatures to remain several
degrees below normal this week.


KEY MESSAGE 2: The risk for high surf and dangerous rip
currents will persist into early this week.

High Surf:
Today: Breaking wave heights will be highest along the
middle/upper Georgia coast through tonight where breakers as
high as 4-6 ft can be expected. Breakers of 3-4 ft will be
common for the lower South Carolina beaches. A High Surf
Advisory is in place through Monday afternoon from Tybee Island
south to Sapelo Island. There will also be a risk for beach
erosion, especially around the times of high tide.

Monday: Strong and gusty NNE winds at daybreak will ease during
the morning and into the afternoon. They`ll also shift to the N
in the afternoon. This will cause breaking waves to decrease,
especially along our GA coast. The High Surf Advisory for our GA
coast is in effect until noon, but it`s possible this may be
dropped sooner if winds and breaking waves are lower than
expected.

Rip Currents:
Today: The rip current risk is high for all beaches due to
elevated winds and seas.

Monday: The combination of strong and gusty NNE winds early in
the morning, decent sized breaking waves, and a longshore
current that could be moderate to strong in strength will bring
a High Risk of rip currents to all of our beaches.

Tuesday and Wednesday: The High risk could continue for
portions of our coast on Tuesday, especially during the morning
hours. This should be followed by an enhanced risk for our GA
beaches on Wednesday.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
18/12z TAFs:
KCHS/KJZI/KSAV: Gusty winds will persist at all terminals
through this afternoon under VFR conditions.

Extended Aviation Outlook: Breezy conditions on Monday should
ease into Tuesday.

&&

.MARINE...
Through Tonight: An earlier ASCAT pass showed solid northerly
gales of 30-35 kt with buoys showing gusts 38-42 kt common
across the marine area. Dangerous marine conditions will persist
across the waters through tonight as the pressure gradient
between strengthening nor`easter off the North Carolina Outer
Banks and high pressure building into the region from the north
remains enhanced. The risk for gales will linger over the
nearshore waters through late afternoon and into the overnight
hours for the offshore waters. Gale Warnings remain in force as
a result. For the Charleston Harbor, winds of 20-25 kt with
gusts to 30 kt with waves 2-3 ft will continue, but begin to
diminish this afternoon into the overnight hours with gusts
finally dropping below 25 kt early Monday morning. A Small Craft
Advisory is in effect until 5 AM Monday. Seas will range from
6-9 ft nearshore and 9-13 ft offshore through tonight.

Monday through Thursday: A nor`easter will be located off well
off the coast of NC Monday morning. Meanwhile, strong High
pressure will be located over the Northeast, with it`s periphery
stretching down into the Southeast U.S. The nor`easter will
very slowly shift away from our region through mid and late this
week. Though, the periphery of High pressure will persist
across the Southeast U.S. The interaction between these two
synoptic features will be generating strong and gusty NNE winds
Monday morning. Winds are expected to ease into Monday
afternoon, followed by a brief surge Monday evening, then
remaining elevated the rest of Monday night into Tuesday
morning. There could be another surge Tuesday evening through
Wednesday morning, before winds become noticeably lower on
Thursday. Seas will be their highest Monday morning, then
gradually subsiding through midweek. Though, the highest waves
will remain in the waters beyond 20 nm. We`ll likely have Small
Craft Advisories in effect on Monday. Though, which marine zones
and for how long will need to be determined with future
forecasts.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...High Surf Advisory until noon EDT Monday for GAZ217-219-239-
     241.
     High Risk for Rip Currents through this evening for GAZ217-219-239-
     241.
SC...High Risk for Rip Currents through this evening for SCZ148>151.
     Lake Wind Advisory until 2 AM EDT Monday for SCZ045.
MARINE...Small Craft Advisory until 5 AM EDT Monday for AMZ340.
     Gale Warning until 5 PM EDT this afternoon for AMZ360-362-364.
     Gale Warning until 5 AM EDT Monday for AMZ380-382-384.

&&

$$