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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KCHS 171409
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1009 AM EDT Tue May 17 2022

.SYNOPSIS...
High pressure will gradually build into the region through the
end of the week. A cold front will approach the region this
weekend, bringing unsettled weather to the area.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
The cold front has cleared the area, allowing high pressure
to build into the region today. No weather concerns with dry
weather and mostly sunny skies. Not much of a drop in
temperature, however it will be less humid than previous days.
Highs are forecast to peak in the upper 80s to around 90.

Tonight: High pressure will prevail with quiet conditions
dominating. The boundary layer will decouple this evening with
light/calm winds prevailing for many areas once the sea breeze
circulation breaks down. Some patchy fog could form early
Wednesday morning across mainly the eastern third of the
forecast area where elevated dewpoints will be left in the wake
of the sea breeze. Lows will range from the lower 60s well
inland and across the Francis Marion National Forest to the
upper 60s/near 70 at the beaches and Downtown Charleston.
-- End Changed Discussion --

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
A strengthening Bermuda High will largely dominate the surface
pattern. Increasing ridging aloft and plenty of dry air above H85
will keep rain chances non-existent through Friday, which will not
help mitigate the current drought conditions across the forecast
area. Some lower-level fair weather cumulus could develop during the
afternoon periods. However, model soundings indicate a slight
subsidence inversion through the period, indicative of a fairly
stable environment.

The most notable feature of the short-term forecast are above-normal
temperatures. Highs are expected to reach the low to mid 90s
Wednesday, cooler at the beaches. Mid to upper 90s are expected for
Thursday and Friday. Some places south of the Altamaha River could
even reach a few degrees shy of 100F Thursday, which is looking to
be the hottest day of the trio. The only sign of respite will occur
from dew points generally ranging 55-60 degrees at the hottest
locations during peak heating, keeping heat indices below 100
degrees.

Warm overnight conditions are expected Wednesday and Thursday with
lows only dipping into the upper 60s to the low 70s. There is a
possibility that new record highs and/or record high min
temperatures could be set Thursday and/or Friday (see the Climate
section below).

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
The next chance for any decent rainfall looks to be Saturday as
return flow advects deep Gulf moisture into the region. A cold front
will then approach the region Sunday and showers/thunderstorms are
possible ahead of the advancing front. Unsettled weather could
persist through early next week as deep moisture lingers and a
potential coastal trough develops. Above normal temperatures will
persist through the weekend before dropping to below normal early
next week.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
KCHS/KJZI/KSAV: VFR will prevail. Shallow ground fog will be
possible at all three terminals early Wednesday morning, but no
major impacts are expected.

Extended Aviation Outlook: Other than the chance of patchy fog
with low vsbys/cigs at the terminals early Wednesday morning,
VFR conditions will prevail through the week. Brief flight
restrictions are possible in showers/thunderstorms over the
weekend.

&&

.MARINE...
-- Changed Discussion --
Through Tonight: North to northeast winds will veer to the east
this afternoon as high pressure builds in from the north and a
sea breeze develops along the coast. Speeds will average 10-15
kt, although locally higher winds will be possible along the
land/sea interface and Charleston Harbor as the sea breeze moves
inland. Seas will average 2-4 ft. Fairly light south to
southeast winds of less than 10 kt will dominate tonight with
seas 2-3 ft.

Wednesday through Sunday: Surface high pressure will prevail across
the southern Atlantic. Benign marine conditions are expected
initially with light winds generally 10 knots or less. By Thursday
morning, southwest winds will increase through the day as the
pressure gradient briefly pinches across the waters. By Thursday
evening, gusts could reach up to 25 kt and Small Craft Advisories
could be needed through the night. Thereafter, southwest winds
around 15 knots will prevail. Seas will average 2-3 feet with 4
footers entering the local waters briefly Thursday night.

Rip Currents: There looks to be enough lingering astronomical
influences and wind with the sea breeze to support a moderate
risk for rip currents along the Georgia beaches today. Although
a 2 second, 8 period swell will impact all beaches, slightly
lower winds along the South Carolina coast should keep the rip
current risk generally in the low category.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
Another round of coastal flooding will occur across the coast
with this evening`s high tide cycle. Data support levels
reaching into the moderate level in Charleston Harbor so a
Coastal Flood Advisory will be needed. Farther south, tides are
expected to peak right at or just above minor coastal flooding
levels at Fort Pulaski. A Coastal Flood Advisory may be needed
from Beaufort County, SC, through McIntosh County, GA.

Additional minor to perhaps moderate coastal flooding will be
possible during the late evening high tides through the end of the
week due to astronomical influences, mainly for Coastal Colleton and
Charleston Counties. Although, less favorable southerly winds should
help mitigate the effects of coastal flooding.

&&

.CLIMATE...
May 19 Record High Temperatures:
KCHS: 96/1996
KSAV: 97/1996

May 20 Record High Min Temperatures:
KCHS: 72/1997

May 20 Record High Temperatures:
KCHS: 97/1938
KSAV: 96/2006

&&

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

&&

$$

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