244
FXUS62 KCHS 122233
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
633 PM EDT Wed Jun 12 2024

.SYNOPSIS...
A stationary front will meander near or just off the coast
through the end of the week. High pressure will build in from
the north through the weekend, then shift east early next week.

&&

.NEAR TERM /THROUGH THURSDAY/...
Weak low pressure along the east-central Florida coast will
meander northeast along a stationary front draped just offshore
overnight. The low should become better defined as the night
progresses in response to approaching southern stream shortwave
energy currently propagating east across the Deep South. KCLX
shows scattered showers/tstms over the Gulf Stream in the
vicinity of the front. Some of this activity will meander into
the coastal waters overnight, but should largely remain
offshore. A rogue shower or two could approach the upper
Charleston County coast closer to daybreak, but most areas will
remain rain-free. While inland areas are likely to decouple,
east/northeast winds will persist along the coastal corridor as
low pressure draws closer. This may allow some degree of marine-
based stratocumulus to onshore after midnight. Between ongoing
high cirrus pushing through and some stratocumulus moving
onshore, expect partly to occasionally mostly cloud skies to
occur. Lows from the upper 60s well inland to the upper 70s
along the beaches look on track.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
Thursday and Friday: Aloft, h5 shortwave energy embedded in a weak
longwave trough will slowly shift across the Southeast United States
while a large ridge centered across the Central United States
strengthens and expands east toward the area through early weekend.
At the sfc, a nearly stationary front will linger well offshore,
becoming a focusing mechanism of low pressure attempting to develop
beyond the Gulf Stream while slowly drifting further offshore. The
pattern will support gradually warming conditions late week as the
ridge nudges across the area and ample sfc heating takes place. A
few showers and/or thunderstorms will also be possible across
coastal counties, where low-lvl moisture lingers and perhaps
strongest convergence occurs near the land/water interface. High
temps will range in the upper 80s/lower 90s Thursday, then low-mid
90s Friday away from the immediate coast. Overnight lows will also
remain mild, generally in the upper 60s to lower 70s Thursday night,
then lower to middle 70s Friday night.

Saturday: Any area of low pressure offshore becomes more diffuse
and/or shifts to the northeast away from the region in advance of a
cold front approaching the local area from the west-northwest during
the day. Aloft, a large/expansive ridge will become directly
centered across the Southeast United States while a weak downslope
flow aloft takes place. Strong subsidence associated with these
features will help keep fropa dry and mix out sfc dewpts into the
mid-upper 60s for areas away from the coast heading into peak
diurnal heating. Strong sfc heating under mostly sunny skies along
with compressional heating associated with the arriving front will
support the warmest temps of the week. 1000-850 mb thickness values
suggest high temps in the mid-upper 90s across most areas away from
the coast, and even a few locations touching 100 degrees well inland
across southeast Georgia and southeast South Carolina. These temps
along with mid-upper 60 sfc dewpts support heat index values ranging
between 100-105 degrees, falling just shy of Heat Advisory criteria.
However, a sea breeze circulation shifting inland could temporarily
nudge dewpt/humidity levels higher during peak heating and will need
to be closely monitored for potential Heat Advisory conditions.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A deep layered ridge across the Southeastern U.S. will prevail
through early next week. Surface high pressure will set up across
the Northeast, resulting in return flow helping to wrap the deeper
Gulf moisture around the backside of the high and into the Deep
South. The advection of moisture/instability will support scattered
showers and thunderstorms early next week, mainly during the
afternoon and evening hours when the sea breeze is active.
Temperatures should begin to slightly decrease and trend toward near
normal or slightly above normal.

&&

.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
13/00z TAF Discussion:
KCHS/KJZI/KSAV: VFR for much of the period. Some stratocumulus
could impact the terminals overnight. Current indications are
that no ceilings will be established. Gusty easterly winds will
develop behind the sea breeze during the afternoon Thursday.
Gusts to 20 kt will be possible.

Extended Aviation Outlook: Prevailing VFR conditions are expected at
CHS/JZI/SAV terminals through Saturday, although brief flight
restrictions can not be ruled out for an afternoon shower or
thunderstorm each day. Tempo flight restriction chances increase
Sunday with greater coverage of showers/thunderstorms near a front
departing the area to the south, followed brief flight restriction
possibilities on Monday with afternoon showers/thunderstorms.

&&

.MARINE...
Tonight: Breezy conditions near the coast this afternoon will
diminish as the sea breeze circulation weakens early this
evening. Moderate northeast winds then prevail tonight as low
pressure begins to gradually deepen off the Southeast coast.
Isolated showers and thunderstorms may develop over the coastal
waters late tonight. Seas increase a bit to 2-4 ft overnight
with increasing ENE windswell, with an underlying modest medium
period S to SE swell continuing as well.

Thursday through Monday: Conditions are expected to remain below
Small Craft Advisory levels as sfc high pressure extends across the
region from the north while a nearly stationary front becomes the
focusing mechanism of a more enhanced coastal trough and/or area of
low pressure developing further offshore by the weekend. In general,
northeast winds around 15 kt will become more southerly around 10 kt
or less as the coastal trough/low drifts further offshore and/or to
the northeast and away from the region well ahead of a front
approaching from the west-northwest during the weekend. The arriving
front will be slow to shift south of the area early next week while
high pressure spreads across coastal waters in its wake. East-
northeast winds around 15 kt should return across most waters behind
the front. Seas should average between 2-4 ft late week into early
next week.

&&

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

&&

$$

ST/ACD