North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

549
FXUS62 KCHS 231830
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
230 PM EDT Sat May 23 2026

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

&&

.KEY MESSAGES...
- 1) Increased chances for showers and thunderstorms through the
  weekend, with isolated strong/severe storms possible across
  the interior late this afternoon into early evening.

&&

.DISCUSSION...
KEY MESSAGE 1: Increased chances for showers and thunderstorms
through the weekend, with isolated strong/severe storms possible
across the interior late this afternoon into early evening.

Aloft, h5 vort energy will ripple across the Deep South and
Southeast United States today along the western periphery of an
Atlantic ridge, encountering a moist (PWATs ~1.75 to 2.0 inches) and
increasingly warming environment this afternoon, which will result
in a period of scattered to numerous showers along with embedded
thunderstorms mid-late afternoon into early evening.

Latest mesoanalysis suggests a worked over atmosphere earlier this
morning recovering with sunshine and a southerly flow this
afternoon. Afternoon highs in the mid-upper 80s combined with sfc
dewpts in the low-mid 70s support sufficient instability for
afternoon convection with an axis of MLCAPE near 2000-2500 J/kg
across Southeast Georgia where strongest sfc heating has taken place
with breaks in cloud cover. Deep-layered shear remains somewhat
modest (20-25 kt) today, suggesting unorganized shower/thunderstorm
activity for most areas. However, shear is strongest well inland and
coincides with highest instability, and when combined with forcing
associated with h5 vort energy and an inland progressing sea
breeze could support a few strong/severe storms within multicellular
thunderstorm clusters mid afternoon into early evening (mainly
along and west of the I-95 corridor in Southeast Georgia and
Southeast South Carolina). Most activity should then weaken/erode
as instability wanes due to the loss of daytime heating by mid evening.
The latest 12Z HREF ensemble paintball does highlight a few spots
of updraft helicity (>75 m2/s2) in the noted area above. Low-lvl
lapse rates around 7-7.5 C/km and DCAPE near 500-750 J/kg also
suggest mainly a damaging wind concern should a severe thunderstorm
occur. The Storm Prediction Center continues to highlight the
noted area in a Marginal Risk for severe weather today.

Another concern with convective activity mid afternoon into early
evening is the potential for localized heavy rainfall/minor
flooding. Hires guidance continues to suggest a corridor of heavy
rainfall from Tattnall County, GA to Allendale County, SC, likely
due to northerly storm motions running parallel to a sea breeze
boundary, and therefore prolonging rainfall from multiple rounds of
shower and thunderstorm activity over the noted area. The 12Z HREF
highlights this area with 1-2 inches of rainfall accumulation with
localized amounts of 2+ inches this afternoon through tonight.
Although this will be considered a mostly beneficial rain event in
an area experiencing Exceptional to Extreme Drought, rainfall rates
could become locally excessive during thunderstorms late afternoon
into early evening, and if so could lead to minor flooding issues.
The Weather Prediction Center continues to highlight the noted area
above in a Marginal Risk for excessive rainfall.

On Sunday, conditions are not expected to change much from today,
with comparable temperatures and moisture content. The sea breeze
will again be the focus the initial thunderstorms, then coverage
should expand across inland areas. Locally heavy rainfall is
possible generally along and west of I-95.

Next week, warm and moist conditions persist as the upper ridge
shifts back towards the southeast United States, which should
support a more summer-like pattern with diurnally driven convection
each day, initially along a sea breeze before expanding across
inland areas mid-late afternoon into evening hours. Temps will
remain above normal, with daily highs in the upper 80s/lower 90s and
overnight lows only in the mid 60s to mid 70s, possibly resulting in
record high minimum temperatures.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR conditions should prevail at CHS/JZI/SAV early afternoon with a
southeast wind gusting up to 10-15 kt behind a sea breeze shifting
inland. Chances for showers and thunderstorms increase late afternoon
to early evening timeframe, with the higher chances occurring
at the SAV terminal where TEMPO -TSRA remains between 23Z Saturday
to 03Z Sunday. PROB30 groups have been shortened at CHS/JZI early
evening based on radar and model trends. VFR conditions should
prevail for much of the night and into late morning hours Sunday.
PROB30 groups have been introduced at all terminals between 16-18Z
Sunday for isolated thunderstorms developing along a sea breeze.

Extended Aviation Outlook: TEMPO flight restrictions possible with
showers and thunderstorms at CHS/JZI/SAV terminals during the
afternoon hours Sunday into the middle of next week.

&&

.MARINE...
This Afternoon and Tonight: Onshore flow will prevail along the
western periphery of Atlantic high pressure, with some local
enhancement to southeasterly winds (~15 kt) along the land/sea
interface today, including the Charleston Harbor. Southerly winds in
the 10-15 kt range are likely overnight. Seas will generally range
between 3-4 ft, although could slightly build about a ft during the
night.

Sunday through Thursday: Conditions are forecast to remain below
Small Craft Advisory criteria through at least the middle of next
week, with daily chances for showers and thunderstorms. High
pressure to the east will drive onshore ESE flow each day, with wind
speeds averaging in the 10-15 knot range. Each afternoon and evening
there could be some local enhancement along the land/sea interface
with the diurnal sea breeze. Seas will average 2-4 feet through the
period.

Rip Currents: A modest easterly swell around 3ft/8s and sea breeze
influences each afternoon will keep the rip current risk in the
moderate category at all area beaches through Monday.

&&

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

&&

$$

BRS/DPB