Hanahan, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

898
FXUS62 KCHS 132350
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
750 PM EDT Sun Jul 13 2025

.SYNOPSIS...
Weak high pressure will continue to build across the region
through the week.

&&

.NEAR TERM /THROUGH MONDAY/...
Tonight: Numerous outflow boundaries have spread across the
forecast area this afternoon and evening. Deep convection should
push south of SE GA by late this evening. The rest of the night
appears dry. Some guidance indicates there is some potential for
ground fog during the pre-dawn hours Monday morning. We will
continue to monitor trends in guidance. Low temperatures should
range in the 70s.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
A weak upper-lvl ridge will remain across the Southeast over the
next couple of days. Simultaneously, a surface low will try to
develop off the Georgia and Florida coastline and track west into
the Gulf on Monday night. At the surface, rich moisture will
continue to be advected into the region with PWAT values ~2.0
inches. This will be more than enough moisture to spark up some
showers and thunderstorms each afternoon as the sea breeze pushes
inland. Expect temperatures to be in the mid to upper 90s on Monday,
with upper 80s to low 90s on Tuesday and Wednesday. Heat index
values on Monday will range from 100 to 106 degree in the afternoon
hours (especially in Southeast Georgia). These values remain under
Heat Advisory Criteria (108F), therefore we will not be issuing a
Heat Advisory for Monday at this time. Deep moisture and moderate
instability will support locally heavy rainfall with any shower
and/or thunderstorm that develops, and isolated strong to severe
thunderstorms are possible each afternoon. Overnight lows will
remain mild and only dip into the low to mid 70s (with warmer
temperatures closer to the beaches).

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A deep upper-lvl ridge will develop over the Southeast late this
week through the weekend, as an area of low pressure moves westward
across the north central Gulf. The Bermuda high will continue to
advect an ample amount of moisture across the Southeast with PWAT
values remaining ~2.0 inches throughout the period. With moderate
instability expected to build in the afternoons, expect typical
summertime weather with showers and thunderstorms initiating off the
sea breeze each day. Temperatures will remain slightly above normal
for this time of the year.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
Prior to the 0Z TAFs, thunderstorms were passing within the
vicinity of KSAV. The KSAV TAF will mention of VCTS until 1Z.
The rest of the night should yield dry conditions with light
northeast winds. Some MOS indicates some potential for low
clouds and fog during the pre-dawn hours. Confidence is too low
to mention any fog in the TAFs at this time. Showers and
thunderstorms should remain concentrated well inland of KCHS and
KJZI Monday afternoon. However, deep convection may spread near
KSAV by late in the afternoon, highlighted with a mention of
VCTS by 22Z.

Extended Aviation Outlook: VFR will mainly prevail throughout the
period, however brief flight restrictions are possible within
showers and thunderstorms that develop in the afternoon and/or
evening hours.

&&

.MARINE...
This Afternoon and Tonight: Conditions will remain well below
Small Craft Advisory criteria through this afternoon and
tonight. For the afternoon and evening, winds will flip around
to become southerly under the influence of the sea breeze
circulation with speeds still mostly 10 knots or less. Right
along the land/sea interface speeds could top out in the 10-15
knot range, including Charleston Harbor. Then overnight, winds
will continue to be quite weak, diminishing to less than 10
knots. Seas should average around 2 feet, but could be up to 3
feet around the 20 nm line and beyond. Much like the last few
days, thunderstorms are expected to develop along or just inland
of the coast and then move southward to the coast or out over
the coastal waters. Frequent lightning and strong wind gusts
will be the primary threats.

Monday through Thursday: Expect generally southerly winds at 5 to 10
kt to prevail throughout the period. 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). Southeasterly swell will continue to mix into
the local waters throughout the week. Seas will be 1 to 2 ft, then
increase to 2 to 3 ft on Tuesday evening. Otherwise, no marine
concerns expected.

&&

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

&&

$$

NEAR TERM...NED
SHORT TERM...Dennis
LONG TERM...Dennis
AVIATION...NED
MARINE...CPM/Dennis