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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KCHS 190838
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
438 AM EDT Fri Apr 19 2024

.SYNOPSIS...
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A slow moving front will bring unsettled weather to the region
today through early next week. High pressure will then return
and prevail into the middle of next week.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
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Today: H5 shortwave energy will traverse the local area early this
morning, attempting to produce a few light showers before reaching
the coast by late morning. Although a few sprinkles can not be ruled
out, model soundings continue to indicate a fairly large amount of
low-mid level dry air, suggesting measurable precip not likely to
occur.

Heading into the late morning hours, conditions become/remain dry
with a west-northwest downslope wind in place aloft and sfc high
pressure prevailing across the Southeast for much of the day. Latest
guidance has taken a step back in regards to precip potential
locally, especially in regards to stronger thunderstorm potential
this afternoon. Much of the convection anticipated locally today
should be associated with a seabreeze circulation taking shape by
early afternoon, then gradually pushing inland through mid-late
afternoon. Wind fields are not all that impressive as this occurs
and the bulk of large scale dynamic forcing remains well displaced
to the northwest closer to a sfc cold front making way across the
Midlands late day. However, ample sfc heating will take place and
the downslope wind aloft will also support warmer temps in advance
of the front during the day. High temps in the upper 80s to around
90 degrees away from the coast along with sfc dewpts in the low-mid
60s support modest inability as convection initiates and makes a
gradually push inland, but thunderstorms will likely remain pulse
type in nature and sub-severe with a lack of stronger forcing
present. The bulk of precip coverage should occur across southeast
South Carolina, with peak coverage occurring late afternoon across
far inland areas.

Tonight: Convection experienced during late afternoon hours will
likely wane or diminish early evening due to the loss of diurnal
heating. The first half of the night will likely remain dry across
all areas while weak high pressure lingers across the area ahead of
a cold front slowly approaching toward northwest tier counties of
southeast South Carolina. The flow aloft remains zonal, suggesting
the front will struggle to reach the local area after midnight, but
could produce a few showers/thunderstorms across northern parts of
Berkeley and Charleston Counties before daybreak. Given the timing
of the front late night and the likelihood of it remaining just to
the north while sliding offshore indicates the threat for stronger
thunderstorms to be low. Low temps should remain mild with a light
south-southwest wind in place under clouds, generally in the mid-
upper 60s.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
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A slow moving cold front will linger over the region on Saturday,
with some southward push later in the day and overnight. The morning
hours should be dry then the potential for thunderstorms will
increase as we move later into the afternoon and evening, though
coverage is still a bit uncertain. Shear is only around 20 knots
when instability is maximized, so overall severe threat is low but a
stronger storm cannot be ruled out. Otherwise, high temperatures
creep back up into the upper 80s/around 90 away from the immediate
coast. Lows Saturday night will be in the 60s.

The aforementioned front will still be in the vicinity Sunday
morning, likely extending from off the SC coast down into southeast
GA, before sinking further south with time. Better forcing will
arrive as shortwave energy passes across the region which should
lead to an uptick in precip coverage. PoPs peak 60-80%. Thunder
potential looks to be limited closer to the coast and across
southeast GA. Temperatures will be tricky given much will depend on
positioning of the front, but overall it will be notably cooler than
previous days especially inland and in northern areas. Highs
generally span the 70s, with around 80 near the Altamaha ahead of
the front. Highest rain chances transition offshore Sunday night.
Low temperatures will be in the 50s.

The front will be well to the east on Monday with high pressure
inland. Main upper wave swings through later in the day which could
lead to additional shower development especially along the coast
where deeper moisture resides. High temperatures top out in the mid
to upper 60s.
-- End Changed Discussion --

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
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High pressure will prevail into midweek, before a cold front
possibly passes through Wednesday night/early Thursday. There
doesn`t appear to be a lot of moisture to work with so a dry
forecast was maintained for now.
-- End Changed Discussion --

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
VFR conditions will prevail at CHS/JZI/SAV terminals through 06Z
Saturday. The risk for a shower/thunderstorm at CHS/JZI Friday
afternoon remains too low to include at this time.

Extended Aviation Outlook: A slow moving front could bring
occasional flight restrictions late Saturday through Monday.

&&

.MARINE...
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Today and Tonight: High pressure will remain the dominant weather
feature across local waters into early night before a cold front
approaches from the northwest, eventually shifting offshore after
midnight near or just north of the area. Conditions will remain
quiet through the day, with southwest winds around 10 kt or less
early morning turning more south and gusting to 10-15 kt in the
afternoon as a seabreeze develops, then pushes inland. Even with the
front approaching late tonight, sfc winds should tip back to the
south-southwest during the first half of the night and show signs of
decreasing. The pressure gradient will remain fairly weak for much
of the night, but there could be a slight uptick in southwest winds
late (around 15 kt) as gradient eventually becomes stronger
approaching daybreak. Seas will range between 2-3 ft, but should
gradually build overnight with 4 ft seas possible across offshore
Georgia waters late.

Saturday through Wednesday: South to southwest winds will persist
through Saturday, before a slow moving cold front sinks south
through the waters later in the weekend. Main time period of concern
will be Sunday night through Monday when winds peak in the 15-20 kt
range behind the front. A few gusts to 25 knots will be possible
over portions of the waters. Winds ease on Tuesday with no
additional concerns through Wednesday.
-- End Changed Discussion --

&&

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

&&

$$

NEAR TERM...DPB
SHORT TERM...ETM
LONG TERM...ETM
AVIATION...DPB/ETM
MARINE...DPB/ETM