809
FXUS62 KCHS 121715
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
115 PM EDT Fri Jul 12 2024

.SYNOPSIS...
A weak front will meander across the area through Saturday.
Atlantic high pressure will then rebuild across the area while
a surface trough exists inland Sunday through the middle of
next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Weak low pressure near the coast is expected to drift onshore
through the day. An associated north-south oriented surface
front will also push further inland. Numerous to widespread
showers and thunderstorms were impacting the Charleston tri-
county early this afternoon. This area should remain the focus
for highest shower and thunderstorm coverage through the rest of
the day where better instability and moisture resides. Locally
heavy rainfall remains a concern. Further south across Georgia
should see more isolated to scattered coverage.

Tonight, the sfc low is expected to drift inland and weaken to a
trough. Isolated to scattered showers and thunderstorms may linger
well into the overnight hours, especially across the SC Lowcountry.
Low temperatures are forecast to range in the mid to upper 70s.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
Saturday: Ridging will begin to build into the southeastern states,
while a weak front will remain stalled in the vicinity at the
surface. PWATs will remain slightly elevated, around 2.0 inches,
with showers and thunderstorms possible across the Charleston Tri-
County in the morning hours. Thereafter, precipitation will likely
take a turn towards a typical summertime pattern with scattered to
widespread showers and thunderstorms in the afternoon. With the
ridging building aloft and plentiful sunshine, temperatures are
forecast to reach into the mid to upper 90s across the region. Head
Indices are currently forecast to be 104 to 106F, just shy of the
108F Heat Advisory criteria. Conditions will need to be monitored
closely, and Heat Advisories may be required. Overnight lows will
remain rather mild, only dropping into the mid to upper 70s.

Sunday and Monday: The ridging aloft will weaken as a mid-level
trough swings across the eastern CONUS. The local forecast area will
likely be positioned at the far southern periphery of this trough,
while at the surface a weak front will drift towards the local
forecast area. With the slight extra forcing aloft and the weak
front in the vicinity the region will likely see enough extra
forcing to spur scattered showers and thunderstorms. Some local
enhancement from the afternoon sea breeze could aid these showers
and thunderstorms, with precipitation possibly reaching all the way
to the coast. Temperatures will be quite hot each day, with heat
indices around 105 to 110F. Heat Advisories will likely be required
for roughly along and east of I-95. Overnight lows will remain mild,
with lows only in the mid to upper 70s.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
Ridging will gradually build into the southeastern states, while
shortwave energy will ripple across the Mid-Atlantic states along
the southern periphery of a mid-level trough. At least scattered
showers and thunderstorms will be possible each afternoon, typical
of a summerlike pattern. Outside of precipitation, hot and humid
conditions are forecast early in the week. Heat Advisories may be
required Monday through Wednesday. Head Index values could even
approach Excessive Heat Warning criteria (113F) across portions of
the forecast area on Tuesday.

&&

.AVIATION /17Z FRIDAY THROUGH TUESDAY/...
Numerous to widespread showers and thunderstorms are expected
around the KCHS and KJZI terminals this afternoon. Reductions in
ceilings and visibilities are possible if a direct impact
occurs. Further south at KSAV, coverage is not expected to be as
widespread, but similarly brief flight restrictions are
possible. Convection should wane later this evening and
overnight.

Extended Aviation Outlook: Scattered afternoon showers/tstorms could
produce brief flight restrictions at all terminals through early
next week.

&&

.MARINE...
Today: South to southeast winds are favored through the day as
weak low pressure and a north-south oriented surface boundary
shifts inland. Speeds will be in the 10-15 kt range. Seas will
build to 2-4 ft this afternoon. A few 5 ft waves are possible
across the outer portions of the Charleston County nearshore
waters this afternoon.

Saturday through Tuesday: A pinched gradient could develop over the
marine waters through early next week as high pressure persists
offshore and a trough lingers inland. However, conditions are
expected to remain below Small Craft Advisory criteria. Generally S
winds are forecast, 10-15 knots. Slightly stronger wind speeds are
possible along the direct coastline in association with the
afternoon sea breeze. Seas should average 3 to 4 ft.

Rip Currents: Moderate SSE swell directed mainly north of Cape Fear
will work into Charleston County coast today. The modest increase in
swell will bump the rip current risk to Moderate for the Charleston
County beaches.

&&

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

&&

$$

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