Area Forecast Discussion
Issued by NWS Charleston, SC

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39
882
FXUS62 KCHS 081744
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
144 PM EDT Tue Jul 8 2025

.SYNOPSIS...
Weak high pressure will extend across the area through the
week.

&&

.NEAR TERM /THROUGH TONIGHT/...
This Afternoon: Typical summertime southwest flow regime remains in
place across the region, with the sea breeze poised to push inland
over the next few hours. As noted yesterday, sounding profiles
continue to show ample instability, with PWATs above 2.0 inches.
That being said, overall shear and storm motion remain quite
limited, suggesting pulse type storms would be favored. Outside of
frequent cloud-to-ground lightning and locally heavy rainfall, can`t
rule out the possibility of seeing isolated damaging wind gusts,
especially if wet microbursts occur. While widespread flooding is
not expected at this time, heavy rainfall may still produce minor
flooding in low-lying and poor drainage areas.

In regard to temperatures, latest observations across the region
show values in the upper 80s to lower 90s, with dewpoints in the mid
to upper 70s. Should see these values increase a few more degrees as
we head into the late afternoon, with dewpoints surging closer to 80
degrees near/behind the sea breeze. For the most part, should see
heat index values range between 100 to 108 degrees, though a few
locations across the Charleston Tri-County area may flirt with
advisory level criteria. Nonetheless, do not plan on issuing any
headlines given the short duration of these values.

Tonight: Convection will linger across the interior through about
mid-evening before dissipating with the loss of insolation. Lows
will range from the mid 70s well inland to the mid-upper 70s across
the coastal counties with lower 80s at the beaches and Downtown
Charleston.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
Aloft, a broad ridge extending across the Southeast from the
Atlantic will gradually erode mid-week as h5 vort energy associated
with a shortwave tracks across the Tennessee Valley towards the Mid-
Atlantic and Southeast into late week. At the sfc, the pattern will
resemble a typical summer-like pattern, with the local area nestled
between an Atlantic ridge centered offshore and troughing developing
inland each day. Although wind shear remains weak during this time
frame, ample moisture (PWATs around 2 inches) and sfc heating
supports higher instability, with SBCAPE around 2500-3000 J/kg, low-
lvl lapse rates between -7.5 to -8.5 C/km and modest levels of DCAPE
favoring scattered to numerous shower/thunderstorm activity each
afternoon/evening and the potential for some strong to marginally
severe thunderstorms capable of producing damaging wind gusts,
particularly Wednesday and Thursday when mid-lvl forcing is somewhat
enhanced across the sfc trough inland. Slower storm motions also
suggest the potential for minor flooding during heavy downpours on
Wednesday, although there could be a limited risk for minor flooding
each day due to convection anchored along outflow/boundary
interactions. The latest SPC Day 2 and 3 Outlooks include a Marginal
Risk for severe weather across much of Southeast South Carolina and
Southeast Georgia Wednesday and Thursday, while the WPC Day 2
Excessive Rainfall Outlook includes much of the area in a Marginal
Risk on Wednesday.

High temperatures will reach the upper 80s near the beaches to lower
90s inland on Wednesday and Thursday, then warm 1-2 degrees higher
on Friday. Overnight lows will remain mild, generally in the low-mid
70s inland to upper 70s/around 80 at the beaches and across Downtown
Charleston.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
Aloft, broad troughing will weaken while exiting across the Mid-
Atlantic and Northeast this weekend, allowing a ridge to build back
across the Southeast United States through early next week.
Otherwise, little change is expected in the overall synoptic pattern
and the forecast. Typical diurnal convection will continue with
scattered showers and thunderstorms forming each day in the
afternoon/evening. Highs will be above normal, peaking the mid 90s
most places over the weekend.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
08/18z TAF Discussion: Scattered showers and thunderstorms have
already started to develop across the region, mainly across the
Charleston Tri-County Area. As noted in the past discussion, believe
KCHS has the best chance of seeing impacts, based on the location of
the sea breeze. Thus, have introduced a brief window of TSRA.
Showers and storms should then gradually wane through the evening
with the loss of diurnal heating. Otherwise, could see another brief
period of showers and storms along the coast mid-morning Wednesday,
though confidence remains too low to include anything more than a
PROB30 at this time.

Extended Aviation Outlook: VFR conditions will prevail at
CHS/JZI/SAV terminals. However, brief flight restrictions are
possible each day due to scattered showers and thunderstorms each
afternoon/evening.

&&

.MARINE...
Through Tonight: Southwest winds will back to the south this
afternoon with the sea breeze with southerly winds then holding
through the overnight period. Speeds will generally range from 10-15
kt, but will be closer to 15 kt with gusts to 20 kt near the
land/sea interface and Charleston Harbor near and behind the sea
breeze. Seas will average 2-3 ft.

Wednesday through Sunday: A fairly typical summertime pattern will
remain in place for much of the week with Atlantic high pressure
centered offshore and a weak trough developing inland each day.
Relatively benign conditions are expected across local waters as a
result, with south to southwest winds around 15 kt and seas between
2-4 ft through late week, although gusts up to 20 kt are possible
along the Charleston County Coast and in the Charleston Harbor due
to sea breeze influences each afternoon.


&&

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

&&

$$

NEAR TERM...SST
SHORT TERM...DPB
LONG TERM...DPB
AVIATION...SST/DPB
MARINE...SST/DPB