288
FXUS62 KCHS 030739
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
339 AM EDT Fri May 3 2024

.SYNOPSIS...
Atlantic high pressure will remain across the Southeast through
much of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
This morning: Satellite imagery, surface observations, and
webcams showing some fog and stratus developing across parts of
the area. This is a little later than it was yesterday morning,
and also there is less coverage so far. However, there is a
strong inversion just off the surface, and with dew point
depressions down near or at zero, the fog will expand in
coverage. Since we`re still not certain that there will be
enough dense fog, no Dense Fog Advisory has been issued. The fog
(whether it`s dense or not) will dissipate by 9-10 am since the
depth of the fog is somewhat shallow.

Today: The mid level ridging of recent days will shift off the
coast of the Southeast, while Atlantic high pressure is the main
feature at the surface. The synoptic flow is southeasterly
through the day, resulting in a sea breeze dominant regime.
After fog dissipates, scattered to broken cumulus will prevail,
while varying amounts of cirrus clouds pass through. There will
certainly be sufficient insolation, and temperatures will be
very similar to yesterday. We didn`t go quite as warm as the
1000-850 mb thickness progs, but with a blend of the MOS and
NBM, we arrive at highs in the mid and upper 80s. Coastal
sections will be 5-10F cooler.

A subtle level level impulse will approach from the west-
southwest late in the day, and this will cause isolated to
scattered convection upstream from our Georgia counties to
approach. There will be some interaction of this activity with
the inland moving sea breeze after 3 or 4 pm, where we show
slight chance PoPs close to and west of the US-301 corridor
(Allendale to Tattnall County). There is little buoyancy, plus
limited MLCAPE and shear, so no strong or severe storm will
occur.

Tonight: A better looking short wave trough moves through the
Tennessee Valley and northern Gulf coast. This along with any
outflow boundaries from prior convection in and near the area,
will allow for isolated or scattered showers and a few t-storms
to occur. This is mainly far inland sections. There will be at
least some form of fog again after midnight given the southeast
and south flow in the boundary layer. However, there is likely
too much mid and high level clouds from the nearby convection
for dense fog to occur. We currently have mention of the
"patchy" fog qualifier, and we will monitor for any dense fog
potential. Low temperatures will be several degrees above climo.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
A mid-level ridge axis will push off the Southeast coast Saturday
with passing waves of shortwave energy across the region through the
short term forecast period. High pressure will remain the primary
feature at the surface. Convection should be a bit more active over
the weekend and into Monday with the presence of deeper moisture as
PWATs increase to 1.5+ inches. Coverage of showers/thunderstorms
will be highest in the daytime when instability is maximized, but
with some upper forcing in play activity could linger into the
overnight period. The greatest chances are focused away from the
immediate coast owing to a progressive sea breeze.

High temperatures will generally peak in the low to mid 80s over the
weekend, warming into the mid to upper 80s Monday. Overnight lows
are only expected to drop to the mid to upper 60s, with locations
right along the beaches and Downtown Charleston near 70 degrees.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
Atlantic high pressure will persist through the middle of next week.
Chances for showers/thunderstorms are limited Tuesday as weak
forcing/remnant shortwave energy passes offshore the Mid Atlantic
coast. Beyond Tuesday, rainfall chances are little to none as a
ridge rebuilds overhead. This will allow max temperatures to rise
into the low/mid 90s by mid next week, possibly approaching record
levels by Wednesday/Thursday.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
KCHS/KJZI/KSAV: Fog and stratus are still expected to occur
during the pre-dawn through mid morning, and dense fog and
conditions down near or below airfield minimums are possible
for several hours. Expect there to be updates, but for now we
have the worst conditions at all terminals between 09Z and 13Z.
It`s possible that with a southeast synoptic flow, the fog and
stratus might be mainly inland from KJZI.

VFR will return around 1300-1330Z, and continue into tonight.
There are no concerns for SHRA or TSRA at any the terminals
with the 06Z TAFs.

Extended Aviation Outlook: Scattered showers and thunderstorms
are possible through Monday.

&&

.MARINE...
Today: High pressure from the Atlantic will be the main feature,
and even with sea breeze influences this afternoon, SE winds
will be no more than about 10 kt. Seas will be only around 2
feet. Even though it is light, the onshore flow will keep any
land based fog off the Atlantic. The exceptions will be
Charleston Harbor (especially the northern part of the harbor
near the North Charleston Port) and the Port of Savannah, where
some of the nearby fog from over the land could drift into
those areas early this morning. At this time no Dense Fog
Advisory is planned.

Tonight: Weak high pressure continues across the maritime
community. Once again the SE winds are no more than about 10
kt, with seas just 2 feet. Maybe some fog could impact
Charleston Harbor and the Port of Savannah, as it tries to
expand in from nearby land sections.

Saturday through Wednesday: Atlantic high pressure will maintain
benign conditions over the local waters. Southerly winds in the
morning will back out of the southeast during the afternoon and
evening hours nearly each day as the sea breeze develops. Winds will
average 10-15 kt with seas 2-3 ft.

&&

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

&&

$$

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