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000
FXUS62 KCHS 312222
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
622 PM EDT Tue Mar 31 2020

.SYNOPSIS...
A storm system will track through the SC Lowcountry and GA
Coastal Empire into this evening. Dry high pressure will then
return into the weekend before a weak front possibly impacts
the area early next week.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Update to cancel the rest of the Tornado Watch. The overall
threat for severe storms, especially the potential for
tornadoes, is quickly ending. Pockets of heavy rain will impact
the Charleston metro area over the next hour or so.

Tonight: The deepening surface low will quickly move east of the
area this evening. The chance for thunder will end early, but
with the influence of the mid/upper level trough overhead,
wrap around showers will continue for much of the overnight.
Most of this shower activity will impact areas along and north
to northeast of the Savannah River. Shower activity should be
scattered, and rain chances are held in the 30-50 percent range.
Skies will start to at least partially clear from the southwest,
but should still be mostly cloudy for most of the night. Much
cooler air will steadily filter in through the night, with lows
reaching the upper 40s well inland, ranging to the low to mid
50s at the coast.

Lake Winds: Northwest winds will strengthen across Lake Moultrie
tonight. Frequent wind gusts are expected into the 20-25 knot
range, but should mostly stay below 25 knots. No Lake Wind
Advisory will be issued at this time, but could be needed later
this evening.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
High confidence this period with high pressure bringing a return of
dry weather and mostly cooler than normal temperatures generally in
the 60s/70s during the day and 40s at night. Can`t completely rule
out some sheltered inland spots even getting into the upper 30s
however Wednesday/Thursday nights.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Surface high pressure will shift east into the Atlantic over
the weekend. A weak front could then approach early next week,
however it doesn`t appear to really make it into the area. Dry
conditions are expected on Saturday, then rain chances will
return Sunday and Monday as onshore flow brings moisture back
into the area. Forecast maintains 20-30% PoPs. Temperatures will
gradually warm through the period.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
KSAV: The potential for thunderstorms has passed and its mention
has been removed from the TAF. Showers could still impact the
terminal, but no significant visibility reductions are expected.
A brief period of MVFR ceilings will be possible, mainly late
this evening.

KCHS: A couple lines of strong showers/thunderstorms will move
in around 6 pm. Winds could gust into the 25-30 knot range with
a brief shot of heavy rain. This should quickly pass with just
showers expected by around 7-8 pm.

At both sites: Northwest winds will be gusty at times overnight
with MVFR ceilings prevailing at KCHS through much of the late
night. Prevailing VFR conditions expected by late Wednesday
morning.

Extended Aviation Outlook: Low risk for restrictions Saturday
night/Sunday due to low clouds/showers.

&&

.MARINE...
Tonight: A deepening surface low will quickly push to the east.
As it does and the cold front moves offshore, northwest winds
will surge quickly across the local waters, especially late
tonight. Small Craft Advisories are in effect for all waters,
including the Charleston Harbor. The strongest winds are
expected across the southern South Carolina waters and the
Georgia waters, where frequent gusts to 30 knots are expected.
Conditions should stay below gale force, but can`t completely
rule out an isolated gust to 35 knots. Seas will increase in
response to the strengthening winds, with up to 5 feet out to 20
nm and up to 7 feet in the outer reaches of the outer Georgia
waters.

Wednesday through Sunday: High confidence this period with high
pressure prevailing. The main concern will be the first part of
Wednesday which will feature Small Craft Advisory conditions
for all waters until strengthening low pressure to the northeast
moves far enough away.

&&

.TIDES/COASTAL FLOODING...
Tide levels will be rising later this week into next week due
to astronomical influences from the upcoming full moon and lunar
perigee and also potentially due to meteorological influences
from onshore winds. This could lead to minor saltwater
inundation around times of the early morning high tides starting
next week.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory from midnight tonight to 11 AM EDT
     Wednesday for AMZ330.
     Small Craft Advisory until 11 AM EDT Wednesday for AMZ352-354.
     Small Craft Advisory until 2 PM EDT Wednesday for AMZ350-374.

&&

$$

NEAR TERM...BSH
SHORT TERM...RJB
LONG TERM...ETM
AVIATION...BSH/RJB
MARINE...BSH/RJB
TIDES/COASTAL FLOODING...