740
FXUS62 KCHS 070207
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1007 PM EDT Sat Jul 6 2024

.SYNOPSIS...
A weak front will remain stalled near the area through much of
next week.

&&

.NEAR TERM /THROUGH SUNDAY/...
Radar continues to show areas of convection across the
Southeast U.S. this evening. While the general trend across the
region has been less coverage and weaker convection, that may
not be entirely the case for our area. Local radar imagery
indicates bands of convection across our far inland counties,
moving very slowly to the east. SPC Mesoscale Analysis has
MLCAPEs ~1,000 J/kg across these locations, which may be
underdone. Luckily, DCAPEs here are only a few hundred, so the
severe threat remains low. The expectation is for the
instability to gradually weaken over the next few hours, leading
to diminishing convection. However, high PWAT values remain in
place across the region (almost 2.5" in some locations). So
small boundary interactions and outflows are generating new
convection in this moisture-rich environment. Even the CAMs have
struggled to grasp the convection that is on the radar now, let
alone a few hours from now. So the expectation is a few more
hours of convection across our far inland counties. Weak
steering winds and the high PWATs will support a continued risk
for locally heavy rainfall. Flooding of low-lying and poor
drainage areas remains a concern. The convection will weaken to
stratiform precipitation and then diminish after midnight. Warm
and humid conditions will persist overnight with lows ranging
from the mid 70s well inland to the lower 80s at the beaches and
Downtown Charleston.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
A mid-level ridge present over the forecast area on Sunday will
slowly begin to weaken into Tuesday with shortwaves rippling
across the southeastern states. At the surface a weak front will
linger in the vicinity. The weakening ridge aloft will yield
temperatures in the low 90s through the short term period. With
dew points in the low to mid 70s heat indices will likely only
reach up to 103, shy of Heat Advisory criteria. With the
lingering front in the vicinity significant moisture will be
available, with PWATs upwards of 2.3- 2.4 inches, which would be
close to the maximum PWAT according to SPC Climatology.
Scattered to widespread showers and thunderstorms will be
possible each afternoon, with the threat of heavy rainfall as
PWATs remain elevated. The best coverage for precipitation will
be across SE GA, closer to the stalled front and higher PWAT
values.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The ridging aloft will continue to weaken through the end of
the week, with additional shortwaves rippling across the
southeastern states. Deep moisture will remain in place, with
PWATs well above 2 inches. Scattered to widespread showers and
thunderstorms are forecast each afternoon, mostly driven by a
robust afternoon sea breeze. The current forecast has high
temperatures in the low to mid 90s through the week, resulting
in heat index values between 100 and 106. Heat Advisories later
in the week cannot be ruled out, however at this juncture the
forecast keeps conditions below the 108 criteria.

&&

.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
00Z TAFs: VFR. While some convection could persist well inland
this evening, it`s not expected to impact the TAF sites. Though,
convection could impact KSAV on Sunday, so we introduced a VCSH
towards the end of the TAF time period.

Extended Aviation Outlook: Brief flight restrictions possible in
showers and thunderstorms, particularly during the afternoon and
early evening.

&&

.MARINE...
Tonight: Southerly winds 10-15 kt with seas 2-3 ft will prevail.

Sunday through Thursday: Generally tranquil conditions expected
across the local marine waters through the period. Winds will
average 15 knots or less with seas 2 to 3 ft.

&&

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

&&

$$

NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...