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267
FXUS62 KCHS 231948
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
348 PM EDT Sun Jun 23 2024

.SYNOPSIS...
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High pressure will remain over the western Atlantic through
much of next week.
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&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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This afternoon: A weak surface low remains across Charleston and
Dorchester counties this afternoon with showers and thunderstorms
primarily forming on the eastern flank, or towards the TriCounty.
Another set of convection has formed across interior GA.
Temperatures have also warmed up rather dramatically this afternoon
over interior GA where 1000/ 850 mb thicknesses are approaching 1440
m. In Tattnall and Toombs counties highs are currently sitting just
shy of the 100 degrees.

Tonight: A mid-level weakness was centered just off of the east
coast of the United States this afternoon and is forecast to shear
out and begin to feel the influence of an approaching mid-level
trough. No precipitation is expected tonight. Lows will again span
the 70s to around 80 at the beaches.
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&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
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A broad upper ridge will remain over the central United States
on Monday while a weak shortwave drops through southeast GA/SC
in the afternoon. A weak surface front is forecast to drop
into the area Monday afternoon, potentially providing a focus
for afternoon convection. Fairly unidirectional W flow will
result in a downslope trajectory, not only pushing temps into
the upper 90s but potentially producing subsidence that works
against convective initiation. The offshore winds will also keep
the sea breeze pinned near the coast much of the day, with only
a small amount of inland movement late in the afternoon. 0-6 km
bulk shear expected to be 25-30 kt with SBCAPE around 1,000
J/kg. Given the approaching cold front, there could be some
storm organization along and ahead of the front in the
afternoon, though the downslope flow could limit the overall
coverage. Heat indices are forecast to top out 105-108F in the
afternoon, just shy of Heat Advisory criteria.

The weak upper ridge pattern will transition to a weak trough
over the Southeast Tuesday into Wednesday. At the surface, a
weak surface wave will linger near the area Tuesday, then
dissipate Tuesday night. A relatively typical summertime pattern
is expected both days, with scattered mainly diurnal convection
and highs in the 90s. Forecast heat indices both days top out
just below 108F in a few spots.
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&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
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A potent shortwave will move through Thursday and Thursday
night. On Friday, surface high pressure will be centered over
the Northeast, with a deep onshore flow over the local area.
Fairly good coverage of showers and thunderstorms expected
Thursday and Friday. A deep layered ridge will build over
the area for the weekend, decreasing diurnal convection
coverage.
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&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
KSAV: The center of the surface low is now located over western
Charleston county this afternoon with most of the shower
formation being towards the Charleston terminals. Behind the
surface low, winds have veered around from the northwest with
not much in the way of precipitation expected. A sea breeze will
push inland later this afternoon with winds turning around from
the south/ southeast. Overnight, only some high and mid clouds
will remain with VFR conditions expected. No fog is forecast
tonight as the pressure gradient remains elevated which should
keep winds up. Late Monday morning, winds will again turn from
the west and be 10 to 15 kts. No precipitation is expected
through the morning hours of Monday.

KCHS/KJZI: The center of the surface low is now located over
western Charleston County this afternoon with most of the shower
activity occurring in close proximity to KCHS and KJZI. A sea
breeze will push inland later this afternoon with winds turning
around from the south/ southeast. Showers will likely come to an
end very soon with coverage decreasing through the afternoon
hours. Overnight, only some high and mid clouds will remain
with VFR conditions expected. No fog is forecast tonight as the
pressure gradient remains elevated which should keep winds up.
Late Monday morning, winds will again turn from the west and be
10 to 15 kts. No precipitation is expected through the morning
hours of Monday.

Extended Aviation Outlook: Mostly VFR. However, convection will
bring brief flight restrictions, mainly each afternoon and
evening.

&&

.MARINE...
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A weak coastal low will continue to head northeast this
afternoon with a surface cold front slowly sagging south out of
the Ohio River Valley. This will result in increasing southwest
flow across the waters tonight with gusts reaching Small Craft
Advisory levels.

Extended Marine: A slight gradient enhancement will persist
Monday and Monday night due to the cold front approaching from
the west and high pressure offshore. Wind gusts and seas should
remain just below Small Craft Advisory criteria.

Monday night through Friday, a typical summertime maritime
pattern expected with S or SW winds less than 15 kt and seas no
greater than 4 ft.
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&&

.CHS WATCHES/WARNINGS/ADVISORIES...
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GA...None.
SC...None.
MARINE...Small Craft Advisory from 2 AM to 8 AM EDT Monday for AMZ350.
     Small Craft Advisory from midnight tonight to 8 AM EDT Monday
     for AMZ374.
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&&

$$

NEAR TERM...Haines
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...Haines/JRL
MARINE...Haines/JRL