766
FXUS62 KCHS 112328
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
728 PM EDT Sat May 11 2024

.SYNOPSIS...
High pressure will prevail into Monday. A storm system will
affect the area by the middle of the week. Another system could
arrive later in the week.

&&

.NEAR TERM /THROUGH SUNDAY/...
Early evening update: No significant changes were made to the
forecast. Still some diurnal Cu out there, but fading quickly.
Keeping an eye on another larger band of cloud cover associated
with a weak surface trough crossing the Appalachians that will
slip down through our region later overnight. Most of the cloud
cover has also been fading with loss of heating and downsloping
off the Appalachians. There might be some residual moisture/a
few clouds passing through the region late evening into the
overnight hours, but not expected to have much impact.

Previous discussion...
High pressure centered over the lower Mississippi Valley will
extend across the Southeast U.S. tonight. A weak surface trough
will drop south and approach the I-26 corridor around daybreak
Sunday. The boundary layer will decouple quickly after sunset
with any weak sea breeze that is pinned near the beaches rapidly
breaking down. Diurnal cumulus will dissipate with the loss of
insolation resulting in mainly clear skies. Clear skies, dry
conditions and calm/light winds will promote strong radiational
cooling. The colder side of the 11/12z temperature guidance
envelope was favored with lows ranging from the mid 50s inland
to the mid 60s at the beaches and Downtown Charleston.

Sky conditions will be ideal for watching the aurora tonight.
Refer to the latest aurora forecast from the National Weather
Service`s Space Weather Prediction Center (www.swpc.noaa.gov)
for the latest aurora and geomagnetic storm updates.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY/...
Sunday will be another beautiful day with low humidity,
seasonable temperatures, and a mix of sun and clouds. Highs
peak in the low to mid 80s. Lows Sunday night range from the
upper 50s across the interior to mid/upper 60s at the immediate
coast.

A mid level low and associated surface reflection will track
from the Central Plains towards the East Coast Monday into
Tuesday. Moisture steadily returns back to the area, with PWats
eventually peaking over 1.75 inches which is well above
climatological normals. While isolated to scattered showers and
thunderstorms are possible Monday afternoon, higher coverage is
expected later Monday night and especially on Tuesday when the
better forcing arrives. Convective evolution is still uncertain,
but severe weather potential will bear watching for Tuesday
with forecast wind shear values (perhaps 40+ knots) supportive
of storm organization. Best instability seems to be situated
south of the Savannah River. Highs both days are forecast to be
in the upper 70s to lower 80s. Lows stay in the 60s.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Low pressure system moves off the mid-Atlantic coast Wednesday
into Wednesday night. Showers and perhaps a few thunderstorms
could develop during the day, but coverage should be more
limited with rain chances only in the 20-30% range. Ridging
briefly passes across the region Thursday before the next system
potentially arrives late week into the weekend and brings rain
chances back in the forecast. Temperatures through the period
are generally near to above normal.

&&

.AVIATION /00Z SATURDAY THROUGH THURSDAY/...
KCHS/KJZI/KSAV: VFR through 13/00z Monday.

Extended Aviation Outlook: Showers and thunderstorms could
bring flight restrictions to the terminals Monday afternoon into
the middle of next week.

&&

.MARINE...
Tonight: No concerns. Weak onshore winds will become more
southwest overnight as a subtle surface trough drops in from the
north. Speeds will remain less than 10 kt with seas 1-2 ft.

Sunday through Thursday: No concerns over the marine area for
Sunday into Monday. Winds will increase Monday night into
Tuesday and will remain fairly gusty into Wednesday as low
pressure tracks towards the East coast. Seas also build and
while it looks fairly marginal at this time, there is potential
for a period of Small Craft Advisories over portions of the
waters, especially the outer Georgia and Charleston county
waters. Conditions improve for Thursday.

Rip Currents: A moderate risk for rip currents continues for the
Georgia beaches until 8 PM as rip currents are being reported at
Tybee Island.

&&

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

&&

$$

NEAR TERM...Adam
SHORT TERM...
LONG TERM...
AVIATION...Adam
MARINE...