611
FXUS62 KCHS 060146
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
946 PM EDT Wed Jun 5 2024

.SYNOPSIS...
High pressure will extend across the area through tonight. A
cold front will approach from the northwest on Thursday, then
slowly move through on Friday. High pressure returns for the
weekend, then another cold front will move through Monday.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
While we generally remain under the influence of Atlantic high
pressure at the surface, a short wave aloft found near and north
of the Savannah River will move through between now and 5 am.
So despite the nocturnal environment, the forcing from this
feature, plus PWat of 140-150% of normal, and lingering
boundaries from previous convection, we hold onto isolated to
scattered convection until the short passes offshore by 6 am.
The highest coverage will be mainly across the South Carolina
counties, where we show 30-50%. A southerly flow, elevated dew
points, and partly to mostly cloudy skies will result in a mild
night. Lows will only drop to the upper 60s and lower 70s
inland, mid and upper 70s closer to the coast.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
Thursday: A shortwave trough is poised to ripple through the
southeastern states in the afternoon to evening hours. At the
surface a cold front will be positioned well to the west of the
forecast area. Ahead of the cold front moisture will pool into the
region, with PWATs increasing to around 1.6 inches. A combination of
the increased moisture and forcing from the shortwave and the
approaching cold front should result in decent shower and
thunderstorm coverage in the afternoon. PoPs are generally in the 40-
50% range across the region, decreasing from west to east in the
overnight hours. High temperatures are forecast to reach into the
low to mid 90s, with overnight lows in the low to mid 70s.

Friday and Saturday: Broad troughing will prevail aloft on Friday
and Saturday, while at the surface a cold front slowly pushes
through by Friday night. High pressure will begin building in at the
surface on Saturday. Not much in the way of precipitation is
expected with the cold front, however it will likely bring a
decrease in dew points. A slight chance of showers and thunderstorms
is possible on Friday afternoon, mainly along the coastal counties
associated with the passing cold front`s interactions with the local
sea breeze. PWATs Saturday are forecast to drop below 1 inch on,
with a dry forecast maintained. Temperatures each day are expected
to reach into the low 90s, with overnight lows in the mid to upper
60s, with around 70 at the beaches.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A return to a typical summertime pattern of afternoon showers and
thunderstorms should return late in the weekend and into early next
week. A cold front is expected to approach the forecast area early
next week, with PWATs increasing to around 1.5 inches by mid week.
Isolated to scattered showers and thunderstorms are possible each
afternoon through mid week due to the increased moisture and
interactions with the local sea breeze. Temperatures are expected to
be right around normal to slightly above normal.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
KCHS/KJZI: Since there is a short wave moving through overnight,
we do show the potential for some convection. We include VCTS
from 06-09Z as a result. Otherwise, it`ll remain VFR. The
potential for SHRA/TSRA with the cold front late Thursday
occurs too late in the 00Z TAF cycle, so no mention at this
time. Both sites will become a little gusty ahead of the front
Thursday afternoon, peaking at least near 20 kt.

KSAV: In all likelihood what little convection there is upstream
from the terminal, will stay away through the night. So VFR is
forecast. Also, any SHRA/TSRA with a cold front late Thursday
occurs too late to include this far in advance. There will also
be some gusts Thursday afternoon, at least as high as 15-20 kt.

Extended Aviation Outlook: VFR.

&&

.MARINE...
Tonight: The local waters will be positioned under the western
side of the Bermuda High pressure system, and with just enough
of a gradient in place, southerly winds will be as high as 10-15
kt. There will even be some gusts at times to near 20 kt
through the night. Seas will average 2-3 feet. Mariners can
expect at least isolated t-storms after midnight.

Thursday through Sunday: SW winds on Thursday afternoon will shift
to the NW by Friday afternoon as a cold front slowly pushes through
the region. SW winds will resume by Sunday afternoon. Wind speeds on
Thursday will be slightly elevated, with 15 to 20 knots across the
marine zones. Thereafter, speeds should remain around 10 knots. Seas
are expected to average 2 to 3 ft through the period.

&&

.TIDES/COASTAL FLOODING...
Astronomical tides will remain elevated on Thursday. Although
the wind direction along the coast isn`t ideal for driving large
positive tidal departures, conditions should still be
sufficient to produce departures in the 0.4 to 0.6 ft.
Therefore, the high tide Thursday evening could peak right
around 7.0 ft MLLW in Charleston. Coastal Flood Advisories could
be needed for Charleston and coastal Colleton counties.

&&

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

&&

$$

NEAR TERM...
SHORT TERM...CPM
LONG TERM...CPM
AVIATION...
MARINE...