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000
FXUS62 KCHS 141648
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1248 PM EDT Sun Apr 14 2024

.SYNOPSIS...
High pressure will persist much of this week. A cold front
might impact our area late in the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Early afternoon temperatures are some 5-7F degrees warmer than
the same time yesterday, and on track to easily reach the lower
and middle 80s away from the coast. Closer to the Atlantic the
sea breeze has already formed and will work it`s way slowly
inland. However, with a deep offshore flow, it only looks to
reach about near or not too far inland from US-17 by late
afternoon.

Today: Surface high pressure will stretch from from the Gulf of
Mexico into the southwest Atlantic, while a subtle lee side
trough prevails inland. The pattern aloft features broad ridging
over Mexico and the central states, while we lie within a zonal
flow between the ridge and a broad trough near the Great Lakes
and Northeast. Other than a few cirrus, skies will be sunny, and
this strong insolation and 850 mb temperatures reaching 12-13C,
will support a warm spring day. We didn`t go quite as high as
the pure low level thickness since there will be the formation
of a light afternoon sea breeze. But still enough to get
temperatures into the lower and middle 80s away from the coast.
Deep mixing will allow for dry air aloft to make it down to the
surface this afternoon, generating low RH values down near 25%
inland from the intracoastal.

Tonight: Quiet weather will persist while high pressure extends from
the western Atlantic and troughing takes place across the Mid-
Atlantic states. The gradient between these two features will not be
particularly strong, but should keep a light southwest wind in place
during the night and result in temps that are more mild compared to
the previous night, especially if some cirrus develops with a
passing h25 aloft. In general, lows should range in the mid 50s
inland to upper 50s/lower 60s near the coast.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
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 continue. 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 stop a front approaching
from the north from reaching our area, yielding dry conditions.
Skies will be sunny, with some cirrus increasing late at night. SW
winds during the day 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 be
mild, in the upper 50s far inland, and the lower 60s along the
immediate coast.

Tuesday: The mid-levels will consist of ridging just east of the MS
River Valley in the morning. The ridge will shift eastward, with its
axis becoming located over the East Coast overnight, 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. This will keep a front well to the north of our
area, bringing us dry conditions. Skies will start out mostly sunny
with cirrus increasing during the day. The clouds are expected to
increase during the evening and overnight. Southerly winds during
the day will be followed by a noticeable afternoon sea breeze
quickly moving inland. The combination of warm 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 be
mild, generally in the 60s.

Wednesday: Mid-level ridging over the East Coast should weaken as it
slowly shifts offshore, yielding WSW flow over our area.
Surface High pressure will remain centered over or near Bermuda,
with it`s periphery still stretching into our region. Low pressure
will be moving through the Great Lakes Region. An attached warm
front will remain well to the north of our area, while a cold front
approaches from the distant west. However, this front is not
expected to reach our area, mainly due to the High pushing it away
from us and to the north. So it will be yet another day with dry
conditions. Southerly winds during the day will be followed by an
afternoon sea breeze quickly moving inland. Despite mostly cloudy
skies, the combination of warm 850 mb temperatures and low-level
thickness values still support well above normal highs in the mid
80s, except cooler at the beaches.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
The mid-level ridging axis will shift further offshore Wednesday
night, leading to zonal flow that`ll prevail overhead into Saturday.
The Bermuda High will start to weaken on Thursday, with a front
approaching our area on Friday. Long-term models disagree on whether
the front will slowly move through our area this weekend, or quickly
move through early next week. For this reason, we generally kept our
forecast drier than what the models have, but expect this portion of
the forecast to change. Temperatures will remain well above normal
into Friday, then cool down over the weekend.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR conditions will prevail at KCHS/KJZI/KSAV terminals through
18Z Monday.

Extended Aviation Outlook: VFR.

&&

.MARINE...
This afternoon and Tonight: Quiet conditions will prevail
across local waters through late day due to a weak pressure
gradient associated with high pressure stretched across the area
from the northeast Gulf of Mexico into the western Atlantic.
Winds will become S and SW during this afternoon, peaking
between 10-15 kt at times, mainly near the coast where a
seabreeze circulation develops before shifting inland. Heading
into overnight hours, the pressure gradient could begin to
strengthen a bit between high pressure across the western
Atlantic and troughing across the Mid- Atlantic states,
resulting in an uptick of southwest winds with gusts up to 15-20
kt (strongest across northern South Carolina waters off the
Charleston County coast). Seas will slowly build through
tonight, peaking between 2-4 ft overnight. Seas will be largest
across northern South Carolina waters off the Charleston County
coast and across offshore Georgia waters.

Extended Marine: High pressure will become stationary over or near
Bermuda Monday through at least Thursday. 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 should 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 Thursday. Friday is when a front could approach our
area. Seas should mostly 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...