North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

892
FXUS62 KCHS 191011
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
611 AM EDT Mon Oct 19 2026

.WHAT HAS CHANGED...
The Marine and Aviation sections were updated.

&&

.KEY MESSAGES...
- 1) Below normal temperatures this week as high pressure
  prevails and a powerful nor`easter meanders off the Mid-
  Atlantic coast.

- 2) Risk for high surf will end this morning along much of the
  Georgia coast. High risk for rip currents for all beaches through
  this evening.

&&

.DISCUSSION...
KEY MESSAGE 1: Below normal temperatures this week as high
pressure prevails and a powerful nor`easter meanders off the
Mid- Atlantic coast.

Through Tonight: The synoptic pattern has changed little in the
past 24 hours characterized by a slowly deepening nor`easter
centered about 300 miles southeast of Cape Hatteras and
expansive high pressure building south over the entire
Southeast U.S. and Deep South. The surface cyclone will
gradually become more vertically stacked with its upper-level
counterpart over the next 12-24 hours and gradually occlude
based on the evolution of the 1000-500 hPa thickness ridging
pattern and related gradients.

The nor`easter is forecast to gradually meander offshore of the
North Carolina Outer Banks through tonight. Locally, high
pressure will prevail keeping the dry, fall weather in place
across the Lowcountry and Southeast Georgia. Some low-level
cloudiness spreading in from off the Atlantic this morning will
bring some cloud cover for areas south of I-16 and possibly
along parts of the lower South Carolina coast, but as the main
steering flow gradually backs with time, these clouds should mix
out as even drier air to the north advects into the region.
Sunny to mostly sunny skies are expected with highs warming
into the 67-72 degree range (values right at the Third Quartile
of the 19/01z NBM interquartile range/IQR), warmest along/south
of the I-16 corridor and nudging up into the US-17 corridor into
parts of the Charleston Metro Area. Gusty north winds that have
plagued the region for the past few days will gradually wane
this afternoon as the surface high builds even farther to the
south and the tightest pressure gradient between it and the
nor`easter shifts farther offshore. Much lighter winds are
expected overnight and the boundary layer may even fully
decouple in some locations resulting in light/variable to calm
winds. This opens up the possibility for some modest radiational
cooling to occur given the dry airmass in place and ongoing
clear skies. Lows were adjusted down a bit off the 19/01z NBM as
a result, ranging from the lower 40s well inland and up into
the Francis Marion National Forest to the mid-upper 40s along
the coastal corridor with lower-mid 50s at the beaches and
Downtown Charleston.

Tuesday through Sunday: A nor`easter will be located well off
the coast of NC Tuesday morning. Meanwhile, strong High pressure
will be located north of the Great Lakes region, with it`s
periphery stretching well down into the Southeast U.S. The
nor`easter will very slowly shift away from our region through
Thursday, then accelerate away Friday into the weekend. Though,
the periphery of the distant High will persist across the
Southeast U.S. This will bring our area dry conditions with
sunny skies. MOS, 850 mb temperatures, and low-level thickness
values, support high temperatures in the middle to maybe upper
70s Tuesday and Wednesday, and the lower to middle 70s Thursday
into the weekend. However, the dry conditions, clear skies, and
light to calm winds at night will cause decent radiational
cooling. This will lead to low temperatures that are several
degrees below normal this week.


KEY MESSAGE 2: Risk for high surf will end this morning along
much of the Georgia coast. High risk for rip currents for all
beaches through this evening.

High Surf: The risk for 5+ ft breakers will linger along the
middle and upper Georgia coast through early afternoon. After
that, the risk for high surf wane a bit as seas offshore
gradually diminish. A High Surf Advisory is in effect for the
beaches along the middle and upper Georgia coast through 2 PM.

The last several NWPS runs have shown larger breaking wave
heights (4-7 ft) occurring along the Charleston County beaches
later this afternoon into tonight with the arrival of a more
powerful, higher period (~12 sec) back-swell. This is even as
seas offshore slowly subside. Surf shop reports out of Folly
Beach Sunday reported messy breakers of 3-4 ft, so it would not
take much of an increase in swell period and/or swell power to
breach the 5 ft High Surf Advisory criteria. If these model
trends persist, a High Surf Advisory may need to be issued for
the Charleston County beaches to cover the mid afternoon into
the Tuesday morning time period. Guidance does show breakers
closer to 4-5 ft occurring farther down along the remainder of
the lower South Carolina and Georgia coasts as the long period
swell train works to the southwest, so the need for an advisory
there looks a bit more marginal.

Rip Currents:
Today: The combination of gusty winds and elevated, lingering
back- swell will support a high risk for rip currents at all
beaches through this evening.

Tuesday: Strong and gusty N winds at daybreak will ease during
the morning and into the afternoon. Wave heights will be
subsiding during this time period. However, the distant
nor`easter will be generating a 4-5 ft NE wave at 12-13 seconds
just offshore. We have a Moderate Risk of rip currents for all
of our beaches. However, if the trajectory of these waves change
to more directly impact our beaches, then that may raise the
risk higher.

Wednesday: The risk should lower for our SC beaches as the
waves subside. However, it may remain elevated for our GA
beaches, possibly through the end of the week.

&&

.AVIATION /10Z MONDAY THROUGH FRIDAY/...
19/12z TAFs:
KCHS/KJZI/KSAV: VFR through 20/12z. Satellite shows an area of
stratocumulus just offshore the Charleston County coast. This
may brush KJZI through daybreak. A TEMPO for MVFR cigs may be
needed pending last minute satellite trends. Gustiness will
diminish during the mid- late afternoon hours.

Extended Aviation Outlook: There are no concerns.

&&

.MARINE...
Today and Tonight: Elevated winds and seas will impact the
coastal waters through tonight even as the tightest pressure
gradient between the high building across the Southeast U.S. and
the nor`easter off the North Carolina Outer Banks gradually
shifts farther to the east and northeast. North/northeast winds
should diminish to 15-20 kt with gusts to 25 kt nearshore and
20-25 kt over the offshore waters during the afternoon and
overnight hours. Seas 4-9 ft nearshore, 9-13 ft offshore will
slowly subside to 4-8 ft nearshore, 7-10 ft offshore by late
afternoon into tonight. Small Craft Advisories will be in place
for all nearshore waters through tonight, including the Georgia
offshore waters.

Tuesday through Friday: A nor`easter will be located well off
the coast of NC Tuesday morning. Meanwhile, strong High pressure
will be located north of the Great Lakes region, with it`s
periphery stretching well down into the Southeast U.S. The
nor`easter will very slowly shift away from our region through
Thursday, then accelerate away Friday into the weekend. The
interaction between these two synoptic features will be
generating strong and gusty N winds Tuesday morning. Winds are
expected to ease into Tuesday afternoon, followed by a brief
surge Tuesday evening into Wednesday morning. Winds become
noticeably lower later Wednesday into Thursday.

Seas will be their highest Tuesday morning, then gradually
subsiding into Thursday. Though, the highest waves will remain
in the waters beyond 20 nm. We have Small Craft Advisories in
effect for the waters within 20 nm through Wednesday. Though,
the end time may need to be adjusted based on the future
forecasts of the sea state, especially longer-period NE waves
from the distant nor`easter.

There appears to be another surge of winds and higher seas on
Friday, with the potential for more gales.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...High Risk for Rip Currents through this evening for GAZ217-219-239-
     241.
     High Surf Advisory until 2 PM EDT this afternoon for GAZ217-
     219-239-241.
SC...High Risk for Rip Currents through this evening for SCZ148>151.
MARINE...Small Craft Advisory until 2 PM EDT Wednesday for AMZ360-362.
     Small Craft Advisory until 6 PM EDT Wednesday for AMZ364.
     Small Craft Advisory until 6 AM EDT Saturday for AMZ384.

&&

$$