162
FXUS62 KCHS 150828
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
328 AM EST Fri Nov 15 2024

.SYNOPSIS...
High pressure will prevail through early next week. A cold
front will move through the area mid week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: 15/08z surface analysis showed the cold front well
offshore with deepening low pressure south of Cape Hatteras.
Extensive post-frontal stratus remains in place with ceilings
generally running 700-1200 ft. The 850 hPa cold front is
crossing the area now and should be offshore by daybreak. Mid-
level winds will begin to veer northwest and become downslope
dominated over the next several hours with its passage. This
should allow a steady erosion of the stratus deck with a modest
scouring out expected by sunrise. This scouring will continue
through the remainder of the morning hours with skies expected
to become sunny by this afternoon. Modest cold air advection
will persist through much of the day with highs poised to reach
the mid-upper 60s with a few spots down south near the Altamaha
River possibly reaching 70s.

Tonight: Heights will steadily build aloft as a pronounced upper
ridge extending north out of the Gulf of Mexico builds east.
This will allow surface high pressure centered over the Great
Lakes and Ohio Valley to build south. Although a slight pressure
gradient will linger for much of the night, some decoupling
over the boundary layer could occur late, especially over far
interior areas. This could promote a few hours of modest
radiational cooling prior to daybreak Saturday, especially far
inland. Lows will range from the lower-mid 40s well inland to
the mid 50s at the beaches and Downtown Charleston. A few upper
30s could occur across far interior Southeast Georgia where
radiational cooling will be the strongest.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
High pressure dominates through Monday leading to quiet weather
conditions. The surface high initially over the Great Lakes and
Ohio Valley will drift east and south with time. Aloft, mid
level ridge will extend north over the Southeast through the
period. Forecast remains rain-free with little in the way of
cloud cover as well. Near normal temperatures in the upper 60s
to around 70 on Saturday will warm to the mid 70s by Monday.
Lows will be coolest Saturday night mainly in the low to mid 40s
away from the coast. Not out of the question to see a couple
isolated spots drop into the 30s.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
Mid level ridge will weaken as we head into midweek as a
deepening trough is forecast to move into the eastern CONUS. At
the surface, a cold front will approach the area, likely pushing
through later Wednesday or Wednesday night. Rain chances return
to the forecast as models indicate tropical moisture along with
some shortwave energy ahead of the main trough could
potentially move across the Southeast later Tuesday into
Wednesday. Gusty west winds following fropa should bring an end
to any rainfall. Notably cooler temperatures are expected for
Thursday and beyond.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
15/06 TAF Discussion:
KCHS/KJZI/KSAV: IFR cigs have filled in behind the cold front
and will linger for several more hours before the flow aloft
becomes downslope dominated. Once that occurs, the scouring out
of the low stratus will commence. That looks to occur roughly in
the 09-12 period and TEMPO groups were utilized during this time
to reflect occasional MVFR cigs as the scouring out occurs. VFR
should return at all three terminals by mid- morning Gusty
winds will persist through mid-afternoon.

Extended Aviation Outlook: Prevailing VFR.

&&

.MARINE...
Today: Gusty northwest winds will persist across the waters
today with ongoing post-frontal cold air advection. Winds will
average 15-20 kt with gusts to 25 kt across the nearshore waters
out 20 NM with 20-25 kt over the Georgia offshore waters out
20-60 NM. Direction swill gradually veer more northerly later in
the day as high pressure begins to build into the region. Seas
will average 2-4 ft, except 1-2 ft near the immediate coast for
all legs out 20 NM with 4-6 ft over the Georgia offshore waters.
Small Craft Advisories are in effect for all legs except
Charleston Harbor. For Charleston Harbor, speeds will average 15
kt with gusts to 20 kt early, then diminish to 10-15 kt this
afternoon.

Tonight: Winds will diminish tonight as cold air advection wanes
and high pressure builds south into the Southeast States. North
winds will settle into the 10-15 kt range over the nearshore
waters with 15-20 kt over the Georgia offshore waters. Seas will
hold 2-4 ft, except 1-2 ft near the immediate coast with 4-6 ft
over the Georgia offshore waters. A Small Craft Advisory will
hold for the Georgia offshore waters through the night.

Saturday through Wednesday: Ongoing Small Craft Advisory for
the outer Georgia waters will persist into Saturday night before
seas subside to less than 6 ft. Otherwise, no notable marine
concerns through early next week. Winds and seas will begin to
increase on Wednesday ahead of a cold front but should hold
below advisory levels through the daytime hours.

&&

.TIDES/COASTAL FLOODING...
Tides are on target to reach coastal flooding thresholds across
Charleston and Coastal Colleton Counties with the morning high
tide cycle. A Coastal Flood Advisory continues for moderate
coastal flooding through 9 AM. Expect tides to peak 7.4-7.6 ft
MLLW (moderate) at the Charleston Harbor gage. Tides are
expected to fall just short of advisory thresholds at Fort
Pulaski, but it will be close. Tends will be watched closely
this morning in case a last minute Coastal Flood Advisory is
needed.

Elevated tide levels will continue through the weekend along
the entire southeast South Carolina and southeast Georgia coast,
with the highest tide levels occurring with the morning high
tides. Minor to moderate coastal flooding is anticipated
although there is a risk for major coastal flood levels with the
Saturday morning high tide for Charleston and Coastal Colleton
Counties.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...Coastal Flood Advisory from 5 AM to 9 AM EST this morning for
     SCZ049-050.
MARINE...Small Craft Advisory until 6 PM EST this evening for AMZ350.
     Small Craft Advisory until 11 AM EST this morning for AMZ352-
     354.
     Small Craft Advisory until 1 AM EST Sunday for AMZ374.

&&

$$