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000
FXUS62 KCHS 180232
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1032 PM EDT Wed Apr 17 2024

.SYNOPSIS...
High pressure will persist through the end of the work week. A
cold front is looking to bring a bit more unsettled weather to
our area this weekend. High pressure returns early next week.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Late this evening, regional radar indicated areas of weakening
showers across NC and SC Midlands, streaming east. These weak
showers should slowly dissipate as they track southeast along a
weak backdoor front. Isolated showers may persist late tonight,
reaching portions of the CWA. The observed KCHS sounding
indicated very dry conditions from the sfc up to H6, with RH
values generally between 20-30 percent. Most of the rainfall
should evaporate tonight. However, a few spots could see rounds
of sprinkles. The forecast update will remove SCHC PoPs,
replacing it with several hours of possible sprinkles. Otherwise,
thick high clouds and light SSW winds should limit cooling
tonight to the mid 60s for most locations.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
Larger scale pattern flattens/becomes a bit more progressive across
the CONUS for the latter half of the week as a deeper closed low
skirts across south-central Canada and the Northern Plains region.
Surface high pressure offshore across the Bermuda region will be
weakening through the period. Some semblance of weak "backdoor"
boundary may be sagging down through the region on Thursday while
the southern tail end of a better defined boundary presses into and
potentially stalls across the southeast region later Friday and into
Saturday. Precip chances with these features remain the main
forecast concern.

Thursday/Thursday night: As mentioned, a weak "backdoor" boundary is
looking to sag down through the region early Thursday with little
fanfare, although there could be some lingering nuisance isolated
showers exiting the far reaches of the forecast area early on. But
the main effect will be to suppress much of the high cloud cover
down and out of our area with trend toward increasing sunshine
throughout the day along with well above daytime highs in the upper
80s to around 90F. With the warm temperatures and modestly higher
surface dewpoints, there is some potential for a few pop-up showers
to develop during the afternoon, particularly along an inland
pressing sea breeze and across the tri-county area where low level
moisture/instability will be greatest. We have opted to leave the
forecast dry for now. Dry weather anticipated Thursday night with
temperatures dipping into the 60s.

Friday and Saturday: Remaining warm but with increasing shower
chances. Southern tail end of a second boundary is looking to press
into the region on Friday before slowing/stalling across the
southeast region later Friday and through the day Saturday. Modest
moisture and instability along/ahead of the boundary will lead to at
least some increasing risk for showers and possibly a few
thunderstorms across the region, particularly during the daytime
hours. Of note; forecast soundings across the area on Saturday show
a fair amount of instability and increased winds aloft suggesting at
least the possibility of a couple of stronger storms. We will
continue to monitor forecast trends.

Otherwise, very warm temperatures continue with highs in the upper
80s and lows in the 60s through the period.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Overall zonal flow pattern is looking to remain in place across the
CONUS through the latter half of the weekend before a piece of
northern stream short-wave energy dives out of the Plains and
through the Mid-Atlantic/southeast CONUS region and acts to develop
a bit more troughiness across the east into next week. Secondary
surface wave may be developing in the northern Gulf along the
stalled boundary and lifting up through the southeast states and off
the Carolina coasts Sunday into Monday, and finally acting to
suppress the boundary down into northern Florida. The better rain
chances are still shaping up to be later Sunday/Sunday night as the
surface wave moves up through the region, subject to further
refinement in later forecasts, with showers lingering into Monday.
Sunday has the look of a cool air wedge developing through Carolinas
into Georgia north of the surface wave track, setting the stage for
an abrupt cool down in temperatures as reflected in the latest MAV
guidance (upper 80s Saturday to the lower-middle 70s on Sunday).

Surface high pressure redevelops across the region for Tuesday into
the middle of next week with a subsequent drying trend and
rebounding temperatures.

&&

.AVIATION /03Z THURSDAY THROUGH MONDAY/...
Prevailing VFR through 0Z Friday at KCHS/KJZI/KSAV.

Extended Aviation Outlook: VFR conditions are likely to dominate
through Saturday, although with some increasing shower chances.
Flight restrictions are looking most likely on Sunday with a wave of
low pressure moving through the region.

&&

.MARINE...
Tonight: High pressure will dominate across the local marine
waters tonight, with SW winds around 10 knots expected. A few
gusts around 20 knots are possible along the direct coastline
this afternoon associated with the sea breeze. Seas will
average 2 to 3 feet.

Thursday through Monday: High pressure near Bermuda will remain the
dominant player through at least Thursday with overall south to
southwesterly flow. Winds will be locally enhanced along the coast
during the afternoon into the evening with formation of a sea
breeze. But with gusts 20 knots or less and seas 2 to 3 feet, marine
headlines are not anticipated.

Surface boundary will be pressing into the southeast states later
Friday, potentially stalling across the region into the weekend
before finally pressing through the region late in the weekend into
Monday. Overall southerly/southwesterly flow will persist through
much of the weekend before shifting into the north/northeast
thereafter. Seas remain largely 3 feet or less through much of the
weekend before north to northeasterly flow behind the boundary
leads to building seas early next week.

&&

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

&&

$$

NEAR TERM...NED
SHORT TERM...Adam
LONG TERM...Adam
AVIATION...NED
MARINE...Adam/CPM