-- Discussion containing changed information from previous version are highlighted. --
212
FXUS62 KCHS 270233
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1033 PM EDT Fri Jul 26 2024

.SYNOPSIS...
A cold front will drop south across the area Saturday, followed
by the return of broad high pressure for much of next week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --
Late this evening: Convection has just about ended other than a
few isolated showers and storms. We should remain dry through
the rest of the night for the most part, though we can`t
completely rule out residual boundary interactions kicking off a
shower or two. If there is any convection it should be focused
mostly offshore. Surface analysis shows that the front is still
positioned upstream but should begin to drop in from the north
late tonight. As it does, winds will turn more northerly by
sunrise especially across southeast South Carolina. Lows are
forecast to reach the low 70s inland, ranging to the mid to
upper 70s along the coast. There could again be some patchy fog
late tonight, primarily in areas that received rainfall today.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
Saturday: The region will be positioned under the broad
cyclonic flow aloft between upper ridging centered over the
Florida Panhandle and the sharpening trough propagating off the
U.S. East Coast. A weak cold front will continue to slide south
into Southeast Georgia during the morning hours, becoming
situated south of the Altamaha River by late afternoon-early
evening. Drier air characterized by lower 850 theta-e values
will attempt to advect south during the afternoon hours, but
surface dewpoints looks to remain elevated (70s) with PWATs
holding around 2 inches. The deepest moisture, low- level
convergence and better instability look to occur over Southeast
Georgia, closer the front itself. CAMs have trended slightly
drier over the past 24-hours and the forecast will feature lower
pops again this cycle given this trend. Pops will range from
20% well inland to 30% over south coastal South Carolina with
30-50% over Southeast Georgia, highest across the middle/lower
Georgia coastal counties. Further downward adjustments may be
needed. A risk for locally heavy rain will exist, but storms
look to remain progressive enough to limit any flooding to low-
lying and poor drainage areas. Convection will quickly wane by
early evening with dry conditions expected overnight. Highs will
peak upper 80s/lower 90s away from the beaches with overnight
lows ranging from the upper 60s/lower 70s well inland to the
upper 70s/near 80 at the beaches.

Sunday: Drier air from the north will further infiltrate the
area with the front displaced well to the south and the upper
ridge aloft builds. Dewpoints are expected to mix out into the
mid-upper 60s as high pressure noses in from the northeast with
a few lower 70s noted along the Altamaha River. This coupled
with considerably lower mean moisture values and lower 850 hPa
theta-e should support a considerably lower risk for
showers/tstms--the lowest in some time. Pops will range from 10%
across most of Southeast South Carolina with 20-40% over
Southeast Georgia, highest near the Altamaha River. These too
many prove too high if trends continue. Highs will warm into the
lower 90s away from the beaches with overnight lows ranging
from the upper 60s/near 70 well inland to the upper 70s/near 80
at the beaches.

Monday: Moisture values will begin to creep up as high pressure
slides farther offshore and the low-level flow becomes more
onshore with time. The best chance for afternoon/evening
showers/tstms will be confined across the interior given the sea
breeze should be fairly progressive during the afternoon hours.
Pops were limited to 20-40% away from the immediate coast with
the highest pops clustered over far interior Southeast Georgia
where net instability and low- level moisture will be the
greatest. Highs will warm into the upper 80s/lower 90s.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
The pattern will trend into a more typical diurnally driven
convective pattern for much of next week. Models show a broad
mid-level weakness developing by mid-week which could help
enhance convection a bit with convection concentrating inland
each afternoon/evening ahead of the sea breeze. Chance pops look
reasonable through period, close to climatological normals for
deep summer. Temperatures will generally run near seasonable
normals, but there are signals the heat and humidity will begin
to build Thursday into Friday.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
At 03z, the risk of thunderstorms at the terminals has ended
for the night. Model guidance continues to hint at a period of
MVFR ceilings starting in the early morning hours as a front
pushes in from the northeast. Any period of MVFR or lower
ceilings could last through mid morning. Winds will be more
northeasterly on Saturday and the potential for thunderstorms
will be significantly less than the last few days.

Extended Aviation Outlook: A typical late summer shower/tstm
regime will dominate for much of the period with
afternoon/evening showers/tstms potentially posing a risk to
KCHS, KJZI and KSAV.
-- End Changed Discussion --

&&

.MARINE...
The surface pattern should support southwest winds between 10
to 15 kts across the marine zone this afternoon. Seas are
forecast to range between 2-3 ft.

A weak cold front is forecast to push over the coast waters
before dawn Saturday. Ahead of the cold front, winds will remain
from the southwest between 5 to 10 kts. In the wake of the
front, winds will turn from the west around 10 kts. Seas should
remain between 2 to 3 ft.

Saturday: A cold front will slip south through the waters
Saturday resulting in winds turning north to northeast during
the day. Speeds in the South Santee-Edisto Beach nearshore leg
could see speeds as high as 15 kt with gusts to 20 kt by
Saturday night. Otherwise, speeds will hold less than 15 kt
across all remaining waters.

Sunday through Wednesday: Winds will turn easterly for Sunday
as high pressure to the north slides offshore. More southerly
winds return by mid-week as the waters become situated along the
western flanks of Atlantic high pressure. Speeds look to remain
less than 15 kt through the period with seas less than 4 ft,
although a few 5 footer could brush the Georgia offshore waters
near 60 NM at times Sunday into Sunday night.

&&

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

&&

$$

NEAR TERM...BSH
SHORT TERM...
LONG TERM...
AVIATION...BSH
MARINE...