Area Forecast Discussion
Issued by NWS Charleston, SC

Home |  Current Version |  Previous Version |  Graphics & Text |  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 40 41 42 43 44 45 46 47 48 49 50
262
FXUS62 KCHS 031039
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
639 AM EDT Wed Jul 3 2024

.SYNOPSIS...
A weak front will linger near the area today. Through the rest
of the week, a hot and humid air mass will build over the
region. A weak cold front could approach the region by early
next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: Aloft, prominent upper ridging will become centered
across an area from east Texas to the Southeast coast. At the
surface, high pressure will start the day wedged in across
Georgia and the Carolinas with the weak boundary still lingering
along and just off the coast. Through the day, the boundary
will wash out as the surface high slips off the east coast. The
most active part of the day will be the morning, as subtle
convergence near the weak boundary generates showers within and
airmass with precipitable water values of 2-2.25 inches. Most of
the shower activity will be focused across the coastal waters
and along the immediate coastline during the morning. There
could still be a few pockets of heavy rain along the coast, but
these should be isolated in nature. Then into the afternoon, the
upper ridge steadily builds in aloft and model soundings aren`t
particularly impressive. The suite of hi-res model guidance
favors southeast Georgia with only isolated convection, and we
have decreased rain chances to reflect less coverage.
Temperatures will be much more typical of early July with low
90s inland and upper 80s along the immediate coast.

Tonight: Overall, a quiet night is expected as see little to no
overnight convection. The boundary we have been dealing with
for the last few days will no longer be present and we carry a
dry forecast for the forecast area. Look for lows in the low to
mid 70s.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
A mid level ridge will extend across the region late week into
the weekend. A closed low over the Atlantic will drift westward
towards the Southeast coast late. The surface pattern will
largely feature high pressure offshore and trough of low
pressure inland. A weak front will approach the region on
Saturday but will stay well west of the local area.

The weather should be fairly quiet for Independence Day and
Friday with influence of the ridge helping to limit convection.
Just isolated showers and thunderstorms are forecast. Saturday
should be a bit more convectively active, especially inland,
with better instability and possibly some weak upper support.
There could be development with the sea breeze, but it appears
most will trigger off the inland trough and then move into the
local area from the west. Rain chances peaking 40-50% in these
locations seems reasonable.

Temperatures will rise with time. Highs in the low to mid 90s
Thursday will warm to the mid to upper 90s away from the
immediate coast for Friday and Saturday. It will feel even
hotter with heat indices approaching the local Heat Advisory
criteria of 108 in spots. Friday looks more marginal, with
Saturday having the better chance for excessive heat headlines.
Lows average in the mid to upper 70s.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
Ridging generally prevails aloft early next week in between a
mid level trough to the west and closed low over the Atlantic
which should eventually weaken. Surface pattern maintains high
pressure offshore and troughing inland. Guidance indicates PWats
exceeding 2 inches through much of the period. At least
scattered showers and thunderstorms will be possible each day,
with highest coverage in the afternoon and evenings.
Temperatures are forecast to stay slightly above normal.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
The 06z TAF period begins with VFR conditions at KCHS, KJZI,
and KSAV. The biggest concerns through the overnight will be
showers and MVFR ceilings at KSAV and possibly KJZI. Radar
imagery shows shower activity along the Chatham County coast
that could approach KSAV over the next couple of hours. Showers
and possible ceilings are less certain at KJZI, and we have kept
the forecast VFR at both KCHS and KJZI. Other than some coastal
showers in the morning, very little convective coverage is
expected this afternoon and evening.

Extended Aviation Outlook: Brief flight restrictions are
possible in showers and thunderstorms, mainly in the afternoon
and evenings through the period.

&&

.MARINE...
Today and tonight: North-northeast flow should prevail across
the local waters through the period. Wind should be strongest
today, focused along the coast with the development of the
afternoon sea breeze. Speeds should mostly be 10-15 knots, with
gusts up to 20 knots along the coast. Overnight, speeds should
drop off to 5-10 knots late. Seas are expected to average 2-4
feet.

Thursday through Monday: Northeast/east winds initially will
turn southerly by late week. Marine conditions should stay
solidly below small craft advisory criteria with speeds 15 knots
or less and seas averaging 2-3 feet.

Rip currents: Longer period swell and the approaching new moon
will lead to an elevated risk for rip currents on Thursday.
Local calculations give borderline low-moderate risk, but given
the Independence Day holiday, opted for moderate.

&&

.TIDES/COASTAL FLOODING...
Onshore winds and the approach of the new moon will lead to
elevated tides over the next couple of days along the Charleston
and Colleton county coasts. Tides levels could approach minor
coastal flooding criteria of 7 ft MLLW in the Charleston Harbor
with the evening high tides today and Thursday. Further south,
no tide issues are expected.

&&

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

&&

$$

NEAR TERM...BSH
SHORT TERM...ETM
LONG TERM...ETM
AVIATION...BSH/ETM
MARINE...BSH/ETM