075
FXUS62 KCHS 021557
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1157 AM EDT Thu May 2 2024

.SYNOPSIS...
Atlantic high pressure will remain across the Southeast through
much of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
No major changes were made for the noon update. The forecast is
on track.

Today: Expect a healthy cumulus field to develop as
temperatures rise. Any cumulus should scour out later this
afternoon as the sea breeze moves inland. Forecast soundings are
not as capped as what was depicted yesterday, but still expect
a rain-free day for most areas. Will need to watch for a few
brief pop ups near the sea breeze where dewpoints will pool back
into the upper 60s/near 70. Gridded pops were held below
mentionable thresholds for now. It should be noted a few of the
CAMs do depict isolated showers/tstms, mainly over Southeast
South Carolina where convergence along the sea breeze will be a
bit stronger. Typically, convergence along a pure sea breeze
circulation is not as strong as a resultant sea breeze, so this
will be watched carefully. Highs from the upper 80s/near 90
inland with cooler conditions closer to the beaches look on
track.

Tonight: Very little change to the pattern surface and aloft.
Winds will quickly decouple this evening, allowing for good
radiational cooling to occur. Actual lows will be similar to
what they were early this morning. Subsidence aloft and
considerable boundary layer moisture will again lead to fog
developing after midnight. For now we show areas of fog all
counties, but dense fog is likely, and another Dense Fog
Advisory could be required. We included mention in the
Hazardous Weather Outlook.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
Shortwave ridging will persist Friday, though the ridge axis
will move off the coast during the afternoon. Strong mid-level
subsidence is expected to maintain dry conditions over the area,
though we can`t rule out a late day shower or thunderstorm far
inland if something moves in from the west. Highs will be in the
upper 80s except along the coast where prevailing onshore flow
enhanced by an afternoon sea breeze keeps temps in the upper 70s
to lower 80s.

Increasing moisture and a series of shortwaves will move through
Saturday through Sunday. Prevailing onshore flow should produce
a robust sea breeze that will move inland fairly early in the
afternoon both days. Scattered to numerous showers and tstms are
expected, especially farther inland where the sea breeze
interacts with greater instability. Although activity should
wane overnight, the continuation of upper level energy moving
through Saturday night could sustain at least isolated nocturnal
convection. Highs both days will reach the low/mid 80s except
near the coast where a marine layer will reduce temps.

&&

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
Monday should again feature scattered diurnal convection given a
weak shortwave moving through, coincident with moderate surface
based instability. A strong subtropical ridge will build over
the area Tuesday through late week, bringing dry weather and
unseasonably warm temperatures. Record high temps are not out of
the question on Wednesday. Highs Wednesday and Thursday are
expected to climb well into the 90s.

&&

.AVIATION /16Z THURSDAY THROUGH MONDAY/...
02/18z TAF Discussion:
KCHS/KJZI/KSAV: The main concern is on fog/stratus overnight
into early Friday morning. 12z guidance is trending lower with
both vsbys and cigs later tonight as a warm/moist airmass
remains in place. Synoptically, the pattern will be similar to
last night, so guidance is likely trending in the right
direction. The 18z TAFs for all three terminals will highlight
conditions dropping below each airfield`s respective alternate
minimums by 08z with conditions occasionally dropping right to
or just below airfield minimums in the 09-13z period. It is very
possible all terminals may become completely fogged in early
Friday with vsbys 1/4SM and VV001-002. The need to introduce
lower conditions will be reevaluated with the 00z TAF cycle, but
a lower trend has been initiated with this TAF cycle. VFR should
quickly return once fog/stratus mix out Friday morning, roughly
in the 13-14z period.

Extended Aviation Outlook: Flight restrictions possible in
overnight/early morning fog and stratus. Isolated to scattered
showers and thunderstorms are possible Saturday through Monday.

&&

.MARINE...
Today: The local waters will remain near the western side of
Atlantic ridging, resulting in light winds veering around to the
NE this morning, then to the E-SE this afternoon. Even with
local sea breeze enhancements, speeds will be no more than about
10-15 kt. Seas will hold around 2 ft.

Tonight: The synoptic pattern is basically the same, and E-SE
winds are again no more than about 10 kt, with seas only 2 feet
throughout. As of this time with an onshore flow, fog is likely
not a concern.

Friday through Tuesday: Atlantic high pressure will maintain
benign conditions over the marine area Friday through Tuesday.
SE winds early in the period will steadily switch to S and then
SW. Wind speeds will generally be less than 15 kt with seas no
higher than 4 ft. The pattern will favor a good sea breeze each
afternoon along the coast, with winds in Charleston Harbor
potentially gusting 15-20 kt at times.

&&

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

&&

$$