North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

556
FXUS62 KCHS 111850
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
250 PM EDT Sat Jul 11 2026

.WHAT HAS CHANGED...
All sections have been updated.

&&

.KEY MESSAGES...
- 1) Showers and thunderstorms through Tuesday could produce
  locally heavy rainfall and isolated flooding. A few storms
  could also become strong to severe.

- 2) Hot and humid conditions will continue into Sunday.

- 3) Minor coastal flooding is possible during the evening high
  tide cycles Sunday through Wednesday.

&&

.DISCUSSION...
KEY MESSAGE 1: Showers and thunderstorms through Tuesday could
produce locally heavy rainfall and isolated flooding. A few
storms could also become strong to severe.

Through tonight: Another round of thunderstorms is expected
across portions of the area this afternoon and evening. The
environment is quite similar to the last few days as well.
Modifying the 12z KCHS RAOB indicates steep low-level lapse
rates, moderate surface-based instability, and sufficient mid-
level dry air to yield DCAPE values well in excess of 1,000
J/kg. Flow through the column is westerly again, including near
the surface, which will keep the sea breeze less progressive and
pinned along the coast. Dewpoints across southeast GA are
expected to mix out into the mid to upper 60s (along and south
of I- 16), which should keep thunderstorm chances much lower
there. The focus will therefore be along the Savanna River and
to the northeast across our southeast SC counties. Regarding
initiation, it appears the early to mid afternoon with a few
storms starting to develop perhaps along the sea breeze. There
could be a strong to marginally severe storm with these as they
develop, but it looks like the main severe threat will come
later in the afternoon and into the evening. Upstream clusters
of storms are expected to develop across central GA and the SC
Midlands and track east-southeastward toward the area. This is
when the most significant severe threat is anticipated,
primarily in the form of damaging wind gusts. There is also
potential for locally heavy rainfall, and even some flash flood
risk, in areas where storms move across the same areas aligned
within the westerly steering flow. The severe threat could
extend beyond sunset, putting the main time period of concern
roughly 4-10pm.

A weak cold front settling into the region Sunday evening into
Monday will serve as the primary focus for showers and
thunderstorms Sunday into Tuesday. Deep moisture, with
precipitable water values between 2 and 2.5 inches, and weak
steering flow will support efficient rainfall rates and slow
storm motions, increasing the potential for localized flooding.
While weak shear should limit storm organization, sufficient
instability with SBCAPE values on the order of 1500-2000 J/kg
could support a few strong to marginally severe thunderstorms.

Guidance also suggests the potential for a weak surface low to
develop along the nearly stationary front early next week.
Should this happen, enhanced moisture pooling would further
increase the heavy rainfall potential. WPC continues to
highlight the area with a Marginal Risk (Level 1 of 4) for
excessive rainfall each day Sunday through Tuesday. Minor
flooding is possible across low-lying and poor drainage areas,
and metro locations such as Downtown Savannah and Downtown
Charleston.

KEY MESSAGE 2: Hot and humid conditions will continue into
Sunday.

Dangerous heat will continue Sunday before showers and
thunderstorms develop. Afternoon highs in the mid to upper 90s
combined with dewpoints in the upper 70s near the coast will
support peak heat index values around 110-112 degrees. Another
Heat Advisory has been issued for the coastal counties and
Berkeley County on Sunday.

Dew points across inland locations should mix into the lower
70s, keeping peak heat index values around 102-106F. While still
hot in areas away from the coast, heat index values will likely
remain below our Heat Advisory criteria of 108F.

KEY MESSAGE 3: Minor coastal flooding is possible during the
evening high tide cycles Sunday through Wednesday.

Increasing astronomical tides associated with Monday`s lunar
perigee and Tuesday`s New Moon will bring a risk of minor
coastal flooding beginning Sunday evening. The greatest threat
is expected Monday through Tuesday as astronomical tides
continue to increase, mainly along the coastal Charleston and
coastal Colleton Counties. Additionally, heavy rainfall
occurring near or during the time of the evening high tide
cycles could exacerbate flooding.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
The 18z TAF period begins with VFR conditions at KCHS, KJZI,
and KSAV. The main forecast challenge is once again
thunderstorms. The best chance for storms this afternoon and
evening will once again be at KCHS and KJZI. Showers and storms
are already starting to develop back to the west and the
potential for impacts will increase through the afternoon and
into the evening. TEMPO groups have been added at KCHS and KJZI
to account for gusty winds and reduced visibilities within heavy
thunderstorm rains. For now the timing is roughly 21- 01z, but
this could need to be refined with amendments as storms evolve.
Thunderstorm coverage should dissipate by late evening, but
depending on how outflow boundaries evolve there could be some
risk of storms into the early morning hours.

Extended Aviation Outlook: Shower and thunderstorm coverage,
along with risks of associated restrictions, will increase
Sunday through Tuesday.

&&

.MARINE...
Through tonight: Southwest flow will become established across
the local waters this afternoon and strengthen into the evening.
Wind speeds should mostly peak in the 15-20 knot range, but a
few gusts up to around 25 knots will be possible. The strongest
winds are expected along the land/sea interface with the sea
breeze. It is possible that conditions could become marginally
supportive of a Small Craft Advisory for the Charleston County
waters, but the probability is considered low at this time. Seas
should average 2-4 feet. Also, another round of thunderstorms
is expected to develop inland this afternoon and evening. These
storms could eventually reach the coast and the coastal waters,
producing frequent lightning and strong wind gusts through the
late evening hours.

Sunday through Thursday: A weak cold front will gradually
settle into the South Carolina waters Sunday evening into
Monday, causing winds to weaken and become more variable.
Scattered showers and thunderstorms will increase across the
coastal waters Sunday through Tuesday, with a few storms capable
of producing strong to severe wind gusts, frequent lightning,
and locally higher seas. Outside of convection, winds and seas
are expected to remain below Small Craft Advisory criteria.

&&

.CLIMATE...
Record High Temperatures:

July 11:
KCHS: 102/1986
KCXM: 100/2001
KSAV: 103/1980

Record High Minimum Temperatures:

July 11:
KCHS: 80/2016
KCXM: 82/2016

July 12:
KCHS: 79/2020

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...Heat Advisory until 7 PM EDT this evening for GAZ217>219-239-
     241.
     Heat Advisory from 11 AM to 7 PM EDT Sunday for GAZ217>219-239-
     241.
SC...Heat Advisory until 7 PM EDT this evening for SCZ045-148>152.
     Heat Advisory from 11 AM to 7 PM EDT Sunday for SCZ045-148>152.
MARINE...None.

&&

$$