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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KCHS 131916
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
316 PM EDT Thu May 13 2021

.SYNOPSIS...
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High pressure will continue building into the region through
Friday and will remain the primary weather feature into the
middle of next week.
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&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
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Surface high pressure will extend across the region tonight, while
mid level troughing prevails aloft. Quiet and dry weather is
expected. Should be a decent set-up for radiational cooling with
mostly clear skies and light winds. Temperatures will again fall
well below mid-May climatology. Lows are forecast to range from
the upper 40s inland to lower/middle 50s at the coast.
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&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
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Friday through Sunday: Overall, very tranquil conditions will
persist across the forecast area through the weekend. Aloft, nearly
zonal flow will prevail into Sunday, then begin to turn more
anticyclonic as shortwave ridging approaches from the west. At the
surface, high pressure centered north of the area will track
eastward and eventually move off the East Coast. Cool northeasterly
low level flow on Friday and Saturday will turn more easterly and
onshore by Sunday. The forecast is rain free. Plenty of sun, coupled
with increasing low level thickness values should result in a steady
warming trend. Friday highs should top out in the mid 70s, which is
around 8 degrees below normal. By Sunday, upper 70s to low 80s will
be widespread which is still several degrees below normal for mid
May.
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&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
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The long term period will feature a building ridge aloft with high
pressure at the surface generally prevailing through the period.
Overall, there is no significant forcing for ascent and most places
will likely be precipitation-free through mid week. There are some
indications that the potential for isolated convection will increase
in the Tuesday-Thursday period, and 20 percent rain chances are in
the forecast. Temperatures are expected to steadily warm and should
be back into the low to mid 80s by Monday. We will likely see some
upper 80s for inland locations Tuesday through Thursday, though
areas along the immediate coast will be limited by the prevailing
onshore flow.
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&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
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VFR is expected through 18z Friday.

Extended Aviation Outlook: VFR conditions will prevail.
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&&

.MARINE...
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Tonight: Elevated northeast winds are expected to continue tonight
in between high pressure over the eastern CONUS and a weak low
well offshore. Seas will average 4-7 feet, highest beyond 20 nm.
These conditions will maintain Small Craft Advisories over all
marine zones, with the exception of the Charleston Harbor.

Friday through Tuesday: Strong northeast flow will continue on
Friday with gusts to 25 knots and seas 4-6 feet for the
nearshore waters and 5-7 feet for the outer waters. Small Craft
Advisories remain in effect for all waters outside Charleston
Harbor through Friday evening when the nearshore waters will
come down. The advisory for the outer Georgia waters will
continue through much of Saturday due to lingering 6 ft seas.
Thereafter, east to southeasterly winds will top out in the
10-15 knot range through Tuesday. Seas should average 2-4 feet.

Rip Currents: A moderate risk of rip currents continues for all
beaches through Friday. Northeast winds won`t be quite as strong by
Saturday, so the rip risk will likely be right on the threshold
between a low and moderate risk. Will continue to highlight this
possible elevated risk in the Hazardous Weather Outlook.
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&&

.CHS WATCHES/WARNINGS/ADVISORIES...
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GA...None.
SC...None.
MARINE...Small Craft Advisory until 8 PM EDT Friday for AMZ350-352-354.
     Small Craft Advisory until 5 PM EDT Saturday for AMZ374.
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&&

$$

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