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000
FXUS62 KCHS 131357
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
957 AM EDT Sat Apr 13 2024

.SYNOPSIS...
High pressure will persist through much of next week. A cold
front might impact our area late next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: A highly amplified upper trough will continue to
progress further out into the Atlantic, as broad ridging
approaches the local area from the west. At the surface, high
pressure centered across the northern coast of the Gulf of
Mexico will slowly nudge east during the day, eventually
becoming stretched to the southwest Atlantic by late day. Full
sunshine, a deep downslope flow, and late morning temperatures
near or even a tad warmer than the same time yesterday will
support an even warmer day. We still show mid and upper 70s just
about everywhere. Deep mixing will tap into higher winds within
the boundary layer, resulting in west- northwest wind gusts of
15-25 mph at times. This will also cause mixing out of dew
points, as Relative Humidity values drop below 30%, or even down
closer to 20% in some far interior sites. Given the antecedent
wet grounds, no are no fire weather concerns.

Tonight: Quiet weather will prevail with dry high pressure remaining
centered near or just south of the local area through the night. The
pressure gradient will weaken substantially across the area as a
trough continues to shift further away from the region across the
western Atlantic, setting up favorable radiational cooling
conditions locally with light/calm winds in place under clear skies
through the night. In general, low temps should range in the upper
40s inland to low-mid 50s near the coast.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY/...
Sunday: The mid-levels will consist of a trough off the New England
Coast in the morning with ridging over the Central U.S. As the
trough moves away, the ridge will gradually shift eastwards, leading
to northwest flow over our area. At the surface, High pressure will
be located over or near the FL Panhandle in the morning. The High
will pass to our south early in the afternoon, then move far off the
Southeast U.S. coast overnight. The High will bring our area dry
conditions. Skies will be sunny, with some increasing cirrus
overnight. Winds shift to the SW during the day, with a notable sea
breeze developing during the afternoon and then moving inland. The
combination of 850 mb temperatures and low-level thickness values
support above normal highs in the lower 80s to maybe middle 80s,
except cooler at the beaches. Lows will also be mild, in the upper
50s to lower 60s.

Monday: Mid-level ridging over the Plains in the morning will shift
eastward, with its axis becoming located approximately over the MS
River Valley late at night. This will cause heights to rise over our
area and for northwest flow to continues. Surface High pressure will
be over or near Bermuda. But it`s far periphery will stretch into
the FL Panhandle during the day. This will bring our area dry
conditions. Skies will be sunny, with some cirrus increasing late at
night. Another day of SW winds will be followed by a noticeable
afternoon sea breeze moving inland. The combination of rising 850 mb
temperatures and low-level thickness values support well above
normal highs in the mid to upper 80s, except cooler at the beaches.
Lows will remain mild, in the upper 50s, except middle 60s closer to
the beaches.

Tuesday: The mid-levels will consist of ridging moving over the East
Coast, leading to rising heights over our area. At the surface, High
pressure will remain centered over or near Bermuda, with it`s
periphery stretching into our region. The High will continues to
bring our area dry conditions. Skies will start out sunny with
cirrus increasing during the day. Southerly winds will be followed
by a noticeable afternoon sea breeze quickly moving inland. The
combination of rising 850 mb temperatures and low-level thickness
values support well above normal highs in the mid to upper 80s,
except cooler at the beaches.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
The mid-level ridging axis will shift over our region Tuesday night,
then move offshore on Wednesday, leading to zonal flow that`ll
prevail overhead into Friday. The Bermuda High will remain locked in
place and that`ll keep our weather dry and push any fronts or
systems north of our area into Thursday. The summerlike pattern will
keep temperatures well above normal into Thursday. Friday is when a
cold front may move through our region, potentially bringing some
showers and slightly cooler temperatures.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions will prevail at CHS/JZI/SAV terminals through 12Z
Sunday. Gusty W-NW winds up to 15-20 kt are possible at all
terminals, and should persist through about 22Z, before a weaker
pressure gradient associated with high pressure results in
winds becoming light from the W-SW or possibly calm shortly
after sunset.

Extended Aviation Outlook: VFR.

&&

.MARINE...
Today: A trough will remain inland over the Southeast as high
pressure expands east from the northern coast of the Gulf of
Mexico and into the Atlantic late. The gradient slowly relaxes
through the day, leading to W and NW winds of 10-15 kt and
gusty. As a result there are no Small Craft Advisories in
effect. We will have to keep a close watch on winds in
Charleston Harbor, as soundings do show winds up near 25 kt in
the boundary layer. For now we increasing winds to 15 kt with
gusts to 20 kt, which presently does not require an advisory.

Tonight: High pressure will become centered near the area
during the night, leading to even more quiet conditions than
experienced during the day. In general, west winds should weaken
to 5-10 kt across all waters with seas no higher than 2-3 ft
overnight.

Extended Marine: High pressure will be located over or near the FL
Panhandle Sunday morning. It will pass to our south early Sunday
afternoon, then move far off the Southeast U.S. coast Sunday night.
It`ll become stationary over or near Bermuda Monday through the rest
of the week. It`s periphery will be the dominant feature for our
weather, driving our local winds. Each morning expect backing winds,
followed by gusty winds along the land/sea interface in the
afternoon due to the formation of the sea breeze. Gusts could be
around 20 kt in the Charleston Harbor with its passage. Each
evening, winds will veer and increase as some coastal jetting
develops overnight. This pattern looks to remain in place through
the end of the marine period. Seas should generally be 2-3 ft within
20 nm and 2-4 ft for the GA waters beyond 20 nm.

&&

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

&&

$$

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