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000
FXUS62 KCHS 121108
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
708 AM EDT Fri Apr 12 2024

.SYNOPSIS...
High pressure will gradually build across the region into the
weekend, persisting through next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: Aloft, a deep upper low will shift eastward across the
Great Lakes region while a shortwave rotates around it and dives
across the Southern Appalachians and toward the eastern
Carolinas. At the surface, the forecast area will remain well
within the large cyclonic circulation around the surface low
situated across the eastern Great Lakes region. Other than a few
cumulus that could swing through portions of the Charleston
Tri-County region in the afternoon, skies will be clear and the
forecast is dry. The main forecast challenge will be gusty
westerly winds throughout the day. The combination of a tight
pressure gradient and deep mixing profiles will allow the
westerly flow to tap into strong winds just above the surface,
yielding frequent gusts into the 25-30 mph range. Full sun and
expected low-level thickness values will support highs in the
73-75 degree range across the forecast area, which would be
slightly below normal for the day.

Lake Winds: Strong and gusty winds will continue across Lake
Moultrie, as well as along the western lakeshore. Frequent gusts
into the 25-30 knot range are expected and a Lake Wind Advisory
remains in effect through 7 pm.

Tonight: High pressure will spread into the area from the west,
though we will main a relatively tight pressure gradient
through the night. Winds will remain gusty in the evening but
should gradually diminish to be more like 10 mph by late Friday
night. Temperatures are expected to range from the upper 40s
inland to the low 50s along the coast.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
The mid-levels will consist of a trough just off most of the
East Coast Saturday morning with ridings over the Central U.S.
The trough will shift further offshore into Sunday, with the
ridge barely moving to the east. The ridge moves over the MS
River Valley by late Monday. Overall, mainly northwest flow will
prevail over our area. At the surface, High pressure will be
centered over the northern Gulf of Mexico Saturday morning, with
a trough along the spine of the Appalachians. The trough will
shift closer to the coast Saturday evening, then dissipate
overnight. At the same time, the High will gradually shift
eastward, becoming located over or near the FL Panhandle by
Sunday morning. The High will pass to our south Sunday
afternoon, moving off the Southeast U.S. coast by Sunday night,
then closer to Bermuda by late Monday. The High and it`s
periphery will be the dominant feature for our weather, bringing
our area dry conditions.

Saturday WNW winds could be breezy in the daylight hours. But
they`ll ease in the evening and overnight. Skies will be
sunny/clear. Low-level thickness values support high
temperatures generally in the mid 70s, even at the beaches due
to offshore winds. Lows will range from the upper 40s to the mid
50s at the beaches.

Sunday 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 trending
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 skies will be sunny, with SW winds during the day,
followed by another noticeable afternoon sea breeze moving
inland. The combination of 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 /MONDAY NIGHT THROUGH THURSDAY/...
Mid-level ridging will be moving over the MS River Valley
Monday night. It`s axis will shift over our region Tuesday
night, then move offshore on Wednesday, leading to zonal flow
that`ll prevail overhead into Thursday. 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. The summerlike pattern
will keep temperatures well above normal.

&&

.AVIATION /11Z FRIDAY THROUGH TUESDAY/...
VFR conditions will prevail at KCHS, KJZI, and KSAV through 12z
Saturday. Main forecast challenge today will be gusty west
winds. Expect frequent gusts in the 25-30 knot range.

Extended Aviation Outlook: VFR. It could be breezy on Saturday.

&&

.MARINE...
Today through tonight: West to west-southwest winds will remain
elevated and gusty across the waters today. Once the Gale
Warnings come down, Small Craft Advisories will be needed for
all waters for much of the day. The nearshore Georgia waters and
the southern South Carolina waters will see the most
improvement, and sub-advisory conditions are expected there by
midday. Winds will turn more northwesterly overnight and remain
elevated. The advisories will continue for the longest period of
time across the Charleston County waters and the outer Georgia
waters.

Rip Currents: The combination of lingering swell energy and
strong and gusty westerly winds will produce a moderate risk of
rip currents at all beaches today.

High pressure will be centered over the northern Gulf of Mexico
Saturday morning, with a trough along the spine of the
Appalachians. The trough will shift closer to the coast Saturday
evening, then dissipate overnight. At the same time, the High
will gradually shift eastward, becoming located over or near the
FL Panhandle by Sunday morning. The High will pass to our south
Sunday afternoon, moving off the Southeast U.S. coast by Sunday
night, then closer to Bermuda by late Monday, where it`ll
strengthen and remain in place for most of next week. It`s
periphery will be the dominant feature for our weather, driving
our local winds. Expect gusty WNW winds Saturday morning that`ll
ease into the afternoon. A summerlike wind pattern sets up on
Sunday, with morning winds backing, followed by gusty winds
along the land/sea interface in the afternoon due to the
formation of the sea breeze. Gusts could reach 20 kt in the
Charleston Harbor with its passage. Winds then veer in the
evening and overnight, with some weak coastal jetting
developing. This pattern looks to repeat itself through the end
of the marine period. Seas should generally be 2-3 ft.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...Lake Wind Advisory until 7 PM EDT this evening for SCZ045.
MARINE...Small Craft Advisory until 10 PM EDT this evening for AMZ330.
     Small Craft Advisory until 8 AM EDT Saturday for AMZ350-374.
     Small Craft Advisory until noon EDT today for AMZ352-354.

&&

$$

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