North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

493
FXUS62 KCHS 281051
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
651 AM EDT Fri Aug 28 2026

.WHAT HAS CHANGED...
The Aviation Section was updated for the 12Z.

&&

.KEY MESSAGES...
- 1) Scattered to numerous thunderstorms expected each afternoon
  and evening through this weekend. Isolated excessive rainfall
  possible this afternoon along the Interstate 95 corridor.

&&

.DISCUSSION...
KEY MESSAGE 1: Scattered to numerous thunderstorms expected each
afternoon and evening through this weekend. Isolated excessive
rainfall possible this afternoon along the Interstate 95
corridor.

Satellite water vapor showed a mid-level longwave trough extending
from eastern Canada south to the Gulf. East of the trough, a band of
deep moisture covered a large area from the Gulf across the
Southeast U.S. Near term guidance indicates a few vort maxes within
the moisture plume, with the consensus of the guidance indicating
that one or two disturbances tracking over SE GA this afternoon. The
approach and passage of these mid-level features concurrent with the
sea breeze should focus the development of convection. Forecast
soundings indicate PW values around 2.25 inches with warm cloud
depth in excess of 12 kft. In addition, SBCAPE should peak around
1500 J/kg with LFC generally below 3 kft. Showers and thunderstorms
should readily develop along and ahead of the sea breeze and mid-
level disturbances. The forecast will feature PoPs as high as 90%
across the I-95 corridor of GA/SC. Given the high coverage of
convection, storm motions around 15 mph, and the deep tropical
moisture, heavy to excessive rainfall is the primary hazard today.
0Z HREF indicates a large area under 70% for 1"/3hr and 30% for
3"/hr along the I-95 corridor. Based on the timing of the sea
breeze, the heavy rainfall could potentially concentrate in an area
between Savannah to Springfield to Ridgeland. After collaboration
with WPC, a Slight Risk for excessive rainfall was posted for the SC
Lowcountry and most of SE GA. Flood Advisories or Flash Flood
Warnings could be needed this afternoon into early this evening.
Fortunately, forecast soundings indicate that DCAPE values may
remain limited to 800 J/kg or less with freezing levels as high as
15 kft, keeping the risk of severe thunderstorms low.

Weak shortwaves aloft may continue some isolated-scattered showers
and thunderstorms Saturday morning, though we`ll have to see where
the aforementioned front ends up to see how long that may linger.
While there will likely be a break from the rain during the mid-
morning to early afternoon hours, additional showers and
thunderstorms are expected as the anticipated afternoon sea-breeze
pushes ashore. While 1500-2000 J/kg of SBCAPE are anticipated, the
lack of flow aloft should keep thunderstorms from getting well
organized, thus keeping the risk for strong to severe thunderstorms
on the low end. However, given the slow storm motions and
precipitable water values in excess of 2 inches, locally heavy
rainfall cannot be ruled out. HREF has scattered 50-70% chances for
an inch along and west of I-95, decreasing into the 20-30%
probability range for 3 inches. Given the higher amounts of cloud
coverage and chances for rain, high temperatures on Saturday look to
be in the lower to upper 80s across the region.

Expect lighter and less focused rainfall for Sunday and Monday as
weak ridging occurs aloft, with another weak front beginning to move
towards the area from the west. Weak mid-level warm air advection
will bring additional chances for scattered showers and
thunderstorms throughout the period, though the best chances will
occur during the afternoon hours as the expected sea-breeze pushes
ashore. High temperatures on both days will be near-normal, in the
mid 80s to lower 90s on Sunday, marginally warmer on Monday in the
upper 80s to mid 90s on Monday.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
12Z TAFs: Satellite water vapor showed a mid-level longwave
trough extending from eastern Canada south to the Gulf. East of
the trough, a band of deep moisture covered a large area from
the Gulf across the Southeast U.S. Near term guidance indicates
a few vort maxes within the moisture plume, with the consensus
of the guidance indicating that one or two disturbances tracking
over SE GA this afternoon. The approach and passage of these
mid-level features concurrent with the sea breeze should focus
the development of convection. Each TAF will feature a mention
of VCSH around 17-18Z with TEMPOs for TSRA from 18-23Z. KSAV
appears to be a greatest risk for TSRA this afternoon and
evening. Otherwise, TAFs will indicate light west winds before
the sea breeze, shifting from the SSW following the sea breeze.

Extended Aviation Outlook: Showers and thunderstorms will bring
brief flight restrictions through the weekend, especially during the
afternoons.

&&

.MARINE...
Today and tonight: The pressure pattern will generally support
southwest winds between 10 to 15 kts across the marine zones. Wave
heights are forecast to remain between 2 to 3 ft.

Extended Marine: No large-scale marine concerns, with daily chances
for showers and thunderstorms. Weak winds Saturday morning will turn
east-southeasterly by the late afternoon hours, continuing through
Sunday. Winds remain weak to start off the work-week.

&&

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

&&

$$

APT/NED