761
FXUS62 KCHS 200752
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
352 AM EDT Mon May 20 2024

.SYNOPSIS...
High pressure will persist for most of this week. A series of
upper level disturbances should impact our area next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Pronounced short-wave has progressed well out of the Georgia
outer waters along with the bulk of the remaining convection,
although isolated showers along the western periphery of the
circulation continue to rotate down through the coastal waters
and skirting the Georgia coast. Quite a bit of lower cloud cover
also along the northern and western edge of the wave continues
to skirt the coastal areas down through southeast Georgia, but
with drier air/clearing skies slowly working in from the north.
Short-wave trough axis will move further away from the coast
today replaced with sharp upper level ridging and surface high
pressure folding into the Atlantic Coast.

Today: Per radar trends and high-resolution guidance, spotty shower
activity is looking to skirt the southeast Georgia Coast - mainly
around Altamaha - through the early morning hours. Thus we plan
to hold on to isolated pops down that way for just a bit longer.
Cloud cover and the last bit of shower activity will slowly
pull away from the southeast coast over the next several hours
with drier air and N-S clearing skies taking shape this morning.
Forecast soundings do suggest the development of "heating of the
day" Cu later in the morning and through the afternoon and could
lead to period of partly sunny conditions. Cloud cover has been
nudged up accordingly.

Otherwise, a cooler and certainly less humid day is on tap.
Highs in the upper 70s to lower 80s anticipated...coolest along
the coast and around Lake Moultrie.

Tonight: Any diurnal cloud cover will fade quickly this evening
with mainly clear skies anticipated thereafter. Along with
diminishing winds and lower dewpoints, lows will dip into the
upper 50s inland to the middle 60s along the coast.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
Tuesday: A positively tilted mid-level trough will be just off the
Southeast U.S. coast in the morning. It will transition into a cut-
off Low in the evening and overnight. Meanwhile, a ridge will
strengthen over the Southeast U.S. during the day and at night.
Broad High pressure centered to our north in the morning will shift
off the Mid-Atlantic Coast as the day progresses. Though, it`s
southern periphery will continue to be the dominant synoptic feature
for our weather during the day and into the night. Subsidence will
yield dry conditions with mostly sunny/clear skies. High
temperatures should be in the mid 80s, except cooler at the beaches.
Lows should range from the upper 50s far inland to the mid 60s
closer to the coast.

Wednesday: The mid-levels will consist of a cut-off Low meandering
off the Southeast coast, while a ridge prevails over the Southeast
U.S. At the surface, High pressure along the Southeast coast in the
morning will shift offshore into the afternoon. A front will slowly
approach from the north and northwest during the evening and
overnight. Though, it won`t make it near our area as the periphery
of the High remains the dominant synoptic feature. Ongoing low and
mid-level subsidence will continue to bring our area dry conditions
with mostly sunny/clear skies. Expect an inland moving sea breeze
during the afternoon. Highs will peak in the upper 80s, except
cooler at the beaches. Lows should range from the lower 60s far
inland to the lower 70s along the immediate coast.

Thursday: A mid-level ridge over the Southeast U.S. in the morning
will weaken as the day progresses. Surface High pressure just off
the Southeast coast in the morning will move further offshore as the
day progresses. The front to our north and northwest will continue
to approach. However, it won`t make it to our area. This periphery
of the High will bring yet another day with dry conditions. Expect
fair weather cumulus in the afternoon along with a sea breeze. High
temperatures should be in the upper 80s to lower 90s, except cooler
at the beaches.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
Expect west southwest mid-level flow over our region Thursday night.
A weak trough may pass to our north Friday night into Saturday,
possibly followed by weak ridging on Sunday. Surface High pressure
in the western Atlantic Thursday night will shift further offshore
into the weekend. A cold front could approach from the north and
northwest later Friday, then lift north on Saturday. Expect some
diurnal convection on Friday, with convection more likely during the
weekend. High temperatures will be a few degrees above normal each
day.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
KCHS/KJZI/KSAV: MVFR to VFR cloud cover will persist at the
terminals through the overnight, with gradual N-S clearing and
return to VFR conditions by morning. VFR conditions then persist
through the day Monday but with SCT to perhaps BKN "heating of
the day" Cumulus develop late morning and persisting through the
afternoon. Turning clear Monday evening.

Extended Aviation Outlook: VFR.

&&

.MARINE...
Surface high pressure will be building along the Atlantic coast
through today. The resulting tighter pressure gradient across
the coastal waters will continue to produce gustier northeasterly
winds today and tonight. Gusts of 20 to 25 knots will be common
today with seas building to 3 to 5 feet in the nearshore waters
and 4 to 6 feet in the outer Georgia waters. We have hoisted a
Small Craft Advisory for the outer Georgia waters for today
through early evening. It`s a bit more marginal across the
nearshore waters with no headline planned at this time. But we
will continue to monitor conditions for possible expansion of
the SCA as we go through the day.

Extended Marine: NE winds on Tuesday will shift around to the SE by
later Wednesday as High pressure gradually shifts off our coast.
This will lead to a more typical summer wind pattern beginning on
Thursday. That`s when mariners should expect backing winds during
the day, along with stronger wind gusts along the land/sea interface
with the formation of the afternoon breeze. At night, winds should
veer as low level jetting sets up along the coast.

&&

.TIDES/COASTAL FLOODING...
The combination of rising astronomical tides with the upcoming Full
Moon and moderate NE winds will cause tides to be elevated through
the middle of this week. Minor flooding is possible with the evening
high tides tonight through Wednesday along the South Carolina
coast.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until 9 PM EDT this evening for AMZ374.

&&

$$