North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

196
FXUS62 KCHS 230710
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
310 AM EDT Mon Jun 23 2025

.SYNOPSIS...
High pressure will remain across the Southeast U.S. for the
first half of this week, then slowly shift over the Atlantic
thereafter. Hot and humid conditions are expected throughout
the week with rain chances increasing by the second half of
week as surface troughing begins to form over the region.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: Aloft, a large/strong ridge centered across the Mid-Atlantic
states will remain the dominating weather feature extending across
the Southeast United States, leading to warm and mostly dry
conditions locally along the western edge of sfc high pressure
extending from the nearby Atlantic. Large-scale subsidence, strong
sfc heating under sunny/mostly sunny skies and 1000-850mb
thicknesses support highs in the low-mid 90s away from the beaches
this afternoon. Most areas will remain dry, although an isolated
shower/thunderstorm can not be ruled out completely given the summer
like pattern and signs of weak lee troughing developing west of the
local area mid-late afternoon. Despite warm temps, strong low-lvl
mixing into a deep layer of dry air depicted on water vapor imagery
and local model soundings suggest sfc dewpts to lower considerably
during peak diurnal heating inland and thus limit maximum heat index
values generally to 100-105 degrees. Any pooling of moisture along
an inland moving sea breeze could temporarily increase heat index
values a few degrees higher for a 1-2 hr period, primarily away from
the beaches across the Tri-County Area, but heat index values should
remain below Heat Advisory criteria.

Tonight: No significant changes are expected to the overall pattern
in regards to high pressure dominating the weather pattern across
the Southeast. Sfc winds will likely decouple under clear skies for
areas away from the beaches mid-late evening, with the bulk of the
area experiencing light/calm winds during the second half of the
night. Hires guidance depicts considerably less fog potential across
the local area late, but perhaps some shallow ground fog across
Southeast Georgia a few hours prior to daybreak, mainly near the I-
95 corridor closer to the Altamaha River, where lower condensation
pressure deficits reside. Temps will remain mild, with lows
generally ranging in the lower 70s inland to mid-upper 70s closer to
the coast and across Downtown Charleston.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
A strong upper-lvl ridge continues to build over the Southeastern
CONUS throughout the week. According to model guidance, 500MB
heights on Tuesday will be ~598 dam, and then weaken to ~594 over
the next couple days. While these are very high heights for the
region, the highest heights will remain just to the north. However,
this will still produce a strong warming trend for the next couple
of days. Temperatures will climb into the mid to upper 90s on
Tuesday and Wednesday, with heat indices creeping ~105-107 in the
afternoons. As of right now, heat indices remain just below Heat
Advisory criteria (108F), but this will continue to be monitored.
This sort of heat is not uncommon for this time year, however it is
important to remember to stay hydrated and limit outdoor activity
(esp. in the afternoon). With little moisture available and
subsidence filtering into the mid-lvls on Tuesday, this will keep
the forecast fairly dry and uncomfortably hot. Tuesday actually
looks to be the hottest day of the week with temperatures making a
run for the 100 degree mark. Some of the models have been hinting
that a weak surface trough could form over the region sometime on
Wednesday and allow for a cooler day than expected on Thursday with
temperatures reaching into the low 90s. Simultaneously, this feature
might advect enough moisture into the region to allow for some
showers and thunderstorms to develop in the afternoon along the
seabreeze on Wednesday and Thursday. Thus, 20-30% PoPs were added in
the forecast for Thursday and Wednesday afternoon. Overnight lows
will remain mild and only dip into the low to mid 70s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
This strong upper-lvl ridging pattern will finally begin to weaken
by the end of the week as a weak surface trough tries to form over
the region. This will allow for some moisture to return and some
recent ensembles indicate a better chance for rain over the weekend
and into early next week. Temperatures will remain above normal for
this time of the year into the weekend.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR conditions are expected at CHS/JZI/SAV terminals through 06Z
Tuesday. However, shallow ground fog could develop near the
terminals just before daybreak Monday, especially at KSAV, but
no meaningful reductions in vsbys are expected.

Extended Aviation Outlook: With the strong upper-lvl ridge in place
over the Southeast, VFR should mainly prevail throughout the period.
However, there could be brief flight restrictions in the afternoon
hours starting on Wednesday through the end of the week as rain
chances make a return.

&&

.MARINE...
Today and Tonight: Atlantic high pressure will dominate the pattern
across local waters, favoring conditions that remain well below
Small Craft Advisory levels through tonight. In general, south-
southwest winds in the 5-10 kt range this morning will turn south-
southeast and peak around 10-15 kt this afternoon, highest across
the Charleston Harbor and perhaps along beaches as a sea breeze
develops, then shifts inland. Winds should then turn more southwest
by late evening, remaining around 10 kt or less overnight. Seas will
generally range between 1-2 ft.

Tuesday through Friday: As a weak south-easterly swell continues to
filter in, seas will be 1 to 2 ft and then gradually become 3 to 4
ft on Friday afternoon as a more easterly, stronger swell mixes in.
Expect winds at 5 to 10 kt to prevail throughout the period as this
upper-lvl ridge continues to sit over the region. However, by second
half of the week, this ridge will begin to shift offshore as a weak
surface trough scoots its way into the Southeast. It could become a
bit gusty each afternoon with gusts up to 15 to 20 kt as the
seabreeze pushes inland (gusts strongest across the immediate
coastline and the Charleston Harbor).

Rip Currents: A 1.5 to 2 ft, 8 second swell will impact the beaches
through this evening along with a 10-15 kt onshore wind in place.
Given these conditions are similar to yesterday with several rip
currents reported along Tybee Island, GA, a Moderate Risk for rip
currents is in place along Georgia beaches through this evening.

&&

.TIDES/COASTAL FLOODING...
The new moon is Tuesday night, which will yield higher astronomical
tides. Winds should be from the SW, which would limit tidal
anamolies. So while Coastal Flooding (mainly for the Charleston
tide gauge) is not forecasted at this time, it won`t take much
for it to occur, prompting an advisory.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.

&&

$$

NEAR TERM...DPB
SHORT TERM...Dennis
LONG TERM...Dennis
AVIATION...Dennis/DPB
MARINE...Dennis/DPB