North Charleston, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

640
FXUS62 KCHS 301106
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
706 AM EDT Thu Apr 30 2026

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

&&

.KEY MESSAGES...
- 1) Showers and thunderstorms expected to move through
  southeast Georgia and southeast South Carolina this morning
  bringing the potential for gusty winds and locally heavy
  rainfall.

- 2) A disturbance will bring much-needed rain to the region
  Friday night through Saturday, though no significant impacts
  are expected at this time.

- 3) Minor coastal flooding possible with the evening high tide
  cycle each day through Saturday. Coastal Flood Advisories
  could be needed for Charleston and coastal Colleton counties.

&&

.DISCUSSION...
KEY MESSAGE 1: Showers and thunderstorms expected to move
through southeast Georgia and southeast South Carolina this
morning bringing the potential for gusty winds and locally heavy
rainfall.

Aloft, zonal flow is in place from the Desert Southwest to the
Southeast Coast. An well defined shortwave embedded within the
zonal flow will push to the east early this morning and spread
across the forecast area through mid morning. At the surface, a
cold front stretches from the East Texas to the Carolina
Foothills. Ahead of this front, several clusters of convection
are ongoing and tracking to the east within a solid 25-30 knots
of steering flow. The main forecast challenge for the day
revolves around this upstream convection and its eventual
passage through the forecast area later this morning.

There is good agreement among hi-res models that upstream
convection will begin to approach our southeast GA counties in
the predawn hours. There is also good agreement that convective
activity will expand in coverage around the Savannah River and
then spread across southeast SC with high coverage of showers
and thunderstorms from sunrise through the mid morning hours.
Instability isn`t particularly impressive, but enough to
support storm development, but pockets of mid-level lapse rates
approaching 7 C/km and mid- level flow of around 40 knots could
yield a strong to marginally severe thunderstorm. Damaging wind
gusts will be the primary threat. Also of note is the potential
for locally heavy rainfall. The HREF depicts are with 3-hour QPF
mean well in excess of 0.50" with probabilities up to 50% of an
inch or more in 3 hours. The best rainfall potential seems to
align across southeast SC, with lesser amounts expected across
southeast GA.

Convection is expected to shift offshore by late morning. In
its wake, conditions should be pretty stable heading into the
afternoon with the aforementioned front sinking southward. Hi-
res models are in good agreement that the afternoon will be
quiet except for some possible convection further south along
the front for the southeast GA coast.

KEY MESSAGE 2: A disturbance will bring much-needed rain to the
region Friday night through Saturday, though no significant
impacts are expected at this time.

Confidence is increasing that beneficial rains will fall across
the drought-stricken Lowcountry and Southeast Georgia Friday
night into Saturday. A weak area of low pressure looks to
develop along a remnant front draped across the Southeast coast
and along the Florida Panhandle Friday. Deep moisture will
increase with PWATs forecast to reach 1.5-1.7" by daybreak
Saturday. As forcing for ascent increases ahead of a potent
southern stream disturbance, widespread rains will begin to
spread in from the west Friday night and impact the entire area
Saturday. Rain will gradually end from west-east late Saturday
afternoon into the evening hours as the developing surface low
moves away, passing just south of Cape Hatteras and eventually
out into the open Atlantic Saturday night.

There are signals that a corridor of heavier rainfall could set
up across the interior within a region of enhanced lift induced
by a dual-jet structure between the polar jet to the north and
a weaker subtropical jet to the south. Current model guidance
focuses this potential over the SC/GA Midlands, which may clip
the far interior portions of the forecast area. However, the
exact placement of the axis of heavier rain remains uncertain.
Latest NBM guidance shows a 40-60% chance of rainfall exceeding
1.5 inches, and a 15-30% chance of totals exceeding 2 inches for
the entire area. We do not anticipate much of a threat for
flooding at this time, given that soils are parched, and rain
rates should be low enough to minimize the risk of rapid
downpours.

Surface-based instability is virtually nonexistent with the
region likely remaining well embedded in the cold sector, but a
few elevated tstms are certainly possible given the degree of
forcing noted aloft.

KEY MESSAGE 3: Minor coastal flooding possible with the evening
high tide cycle each day through Saturday. Coastal Flood
Advisories could be needed for Charleston and coastal Colleton
counties.

Astronomical tide levels will continue to nudge higher as we
approach the full moon on Friday (5/1). Winds could become more
supportive of large tidal departures starting later today and
continuing through Saturday. The tide level at Charleston is
expected to peak around 7 ft MLLW each evening, and Coastal
Flood Advisories could be needed.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
The 12z TAF period begins with VFR conditions at KCHS, KJZI, and
KSAV but shower and thunderstorm coverage is increasing this
morning. It remains unclear if all 3 sites will take direct hits
from storms based on current radar. KCHS and KSAV might stand
the best chances, but there is enough risk that we have
maintained TEMPO groups for thunder with gusty winds and IFR
conditions. This shower and thunderstorm activity will steadily
work to the east across the area this morning, likely coming to
an end by the late morning hours. Into the afternoon, VFR
and mostly quiet conditions are expected. There could still be
isolated showers and thunderstorms along a cold front as it
drops southward, but confidence in direct impacts is low at this
point.

Extended Aviation Outlook: Flight restrictions are possible
within showers/thunderstorms, especially Friday night into
Saturday as a system moves across the region.

&&

.MARINE...
Through tonight: Southwest flow will prevail across the waters
early this morning ahead of a cold front sagging in. As the
front moves through today, winds across the SC waters will start
to turn more northeasterly with southerly flow across the GA
waters. By tonight, a more uniform northeast flow will take
hold. Winds and seas will both remain well below Small Craft
Advisory thresholds. Likely of more interest is the potential
for thunderstorms this morning along the coast that could
produce strong wind gusts. The main time period of concern is
approximately 5-10am, with the best chance for strong storms
along the SC coast.

There is a risk for winds to reach marginal Small Craft
Advisory levels Saturday as low pressure develops offshore and
pulls away from the region. Gusts to 25 kt may linger over parts
of the offshore waters through Saturday night into early Sunday
morning. Seas look to peak around 3-5 ft within the nearshore
waters and 4-6 ft within the offshore waters late Saturday
afternoon into early Sunday morning.

&&

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

&&

$$

BRS/BSH