Area Forecast Discussion
Issued by NWS Charleston, SC

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845
FXUS62 KCHS 310027
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
827 PM EDT Sat Aug 30 2025

.SYNOPSIS...
High pressure will extend across the area through early next
week while a stationary front lingers just off the coast. A
cold front will move through on Thursday night.

&&

.NEAR TERM /THROUGH SUNDAY/...
Tonight: Surface low pressure will remain quasi-stationary off
of the SC/ GA coast with winds out of the northeast. Some
guidance is showing convection reforming along the coast
overnight. This appears to be due to the surface low remaining
weak with a land breeze pushing inland. Other guidance shows the
coastal low remaining strong enough to keep the land breeze
from forming. Most guidance keeps the surface low strong enough,
to prevent the quasi- stationary land breeze from forming.
Expect low temperatures in the mid 60s (inland) to near 70 at
area beaches.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
Sunday: As a high pressure continues to build into the region from
the north, a nearly stationary front will stall just offshore. Quite
a bit of moisture and mid-lvl support will remain in the region and
will allow scattered to numerous showers and thunderstorm to develop
throughout the day. Majority of the guidance continues to agree that
the greatest coverage will likely occur along and south of I-16.
Additionally, WPC highlighted the immediate coastline under a
Marginal Risk (level 1 of 4) for excessive rainfall.

Monday and Tuesday: A mid-lvl low will attempt to cutoff across the
Mid-Atlantic and allow for subtle waves of h5 vort. energy to be
advected across the Southeast, while this front continues to stall
nearby. This sort of setup will produce additional showers and
thunderstorms along the immediate coastline, however coverage will
be less due to the downward trend of PWATs.

Temperatures will remain below normal this weekend into early next
week as east-northeasterly winds persist and high pressure builds
into the region. Expect highs in the low to mid 80s through early
next week. Overnight lows will range in the mid to upper 60s inland
and low 70s near the coastline.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As the surface high pressure shifts northeastward, another weak low
pressure tries to form offshore on Wednesday and Thursday.
Additionally, deep moisture and isentropic ascent becomes more
favorable across the region, and this will aid in higher afternoon
shower and thunderstorms coverage in the middle of the week.
Thereafter, a cold front approaches the region from the northwest
and unsettled conditions could continue through the end of the week.
Temperatures will remain below normal through the middle of the
week, and then near normal by the end of the week depending on the
strength of the high pressure ahead of the front.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
The 00Z TAFs will feature MVFR cigs to start at KJZI/KSAV and
VFR at KCHS. MVFR cigs are likely to develop over KCHS starting
around 03Z, remaining through the night at all terminals. There
is a chance that KSAV could drop even lower to IFR cigs
overnight, however confidence was too low to go prevailing IFR.
Models keep most of the precipitation offshore tonight and into
tomorrow, however a stray shower is possible along the coastal
corridor, therefore a VCSH has been included in the 00Z TAFs.

Extended Aviation Forecast: Occasional MVFR ceilings possible
through Monday as a weak front remains stalled along the coast,
thereafter flight restrictions are possible with afternoon
showers and thunderstorms.

&&

.MARINE...
Today and Tonight: Coastal low pressure has developed around 40
nm east of Savannah, GA with showers and thunderstorms now
focusing over the coastal waters. A few stronger storms are
possible near the surface low with gusty winds and an isolated
waterspout the primary threats. Wave heights will also start to
build this afternoon towards 2 to 4 ft.

Sunday through Thursday: As the pressure gradient strengthens, east-
northeasterly winds will become rather gusty across the Atlantic
until the middle of the week (w/ gusts up to 25 to 30 kts possible).
Therefore, Small Craft Advisories were issued for all marine zones
beginning on Sunday and lasting until at least Tuesday. Seas will
will range from 5 to 7 ft, and then back down to 2 to 4 ft on
Wednesday morning.

Rip Currents: Due to the increasing strength of the pressure
gradient and the holiday weekend, a moderate risk of rip currents
has been issued for today and tomorrow (Sunday). Also, a high risk
of rip currents has been issued for Monday.

&&

.TIDES/COASTAL FLOODING...
Tidal departures could begin to build over the weekend into early
next week as low pressure develops offshore and a wedge of high
pressure lingers inland. Tides could get close to minor flood
thresholds in the Charleston Harbor by Monday yielding a risk for
coastal flooding across coastal areas of Charleston and Colleton
Counties during mainly the afternoon high tide cycle. This risk may
extend into the middle of next week depending on how strong the
pinched gradient gets.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory from 10 AM Sunday to 2 AM EDT Monday for
     AMZ330.
     Small Craft Advisory from 6 AM Sunday to 8 AM EDT Tuesday for
     AMZ350-352-354.
     Small Craft Advisory from 6 AM Sunday to 8 PM EDT Tuesday for
     AMZ374.

&&

$$

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