841
FXUS62 KCHS 281457
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1057 AM EDT Sun Apr 28 2024

.SYNOPSIS...
High pressure will prevail through much of next week. A weak
disturbance will move through late Tuesday. A weak cold front
could approach next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Today: Aloft, the axis of a mid-upper lvl ridge will extend across
the Southeast United States. At the sfc, the local area will remain
along the western fringes of high pressure centered across the
western Atlantic. The pattern will result in rainfree day across all
areas given the amount of dry air aloft. Cirrus will continue
to stream through the region, while scattered to broken stratocumulus
and flat cumulus will also occur, especially near and along the
inland moving sea breeze. Most areas will still see sufficient
sun that results in max temps quite similar to the previous day.
In general, highs should peak in the upper 70s to lower 80s,
warmest away from the coast.

Tonight: Ridging again prevails both at the surface and aloft.
Winds will decouple quickly this evening, with geostrophic winds
at 1000 mb no more than 5 or 10 kt. With mainly just few-
scattered cirrus for much of the night, this will set up good
radiational cooling. We`ll end up a bit cooler than it was early
this morning, with actual min temperatures close to climo. There
is still enough moisture in the boundary layer to produce some
late night stratus/stratocumulus and maybe a little fog. Since
the bulk of the guidance doesn`t have any reduction in
visibilities, there is no mention of fog in the forecast.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
Deep layered ridging will persist on Monday with dry weather and
a gradual warming trend. Highs should reach the lower 80s away
from the coast, with upper 70s closer to the coast due to a
persistent onshore flow.

A fairly strong upper shortwave will move into southern SC
Tuesday afternoon, accompanied by a slug of moisture. Isolated
showers and tstms are possible mainly in the afternoon.
Increasing thicknesses should yield highs in the mid 80s away
from the coast.

There are some model differences with how quickly the shortwave
moves off the coast Wednesday morning. Decent low-level
convergence expected during the afternoon between prevailing
weak NW flow and a developing sea breeze. Since some of the
guidance is now showing convection on Wednesday, we penciled in
a slight chance PoP inland. The warming trend will continue with
highs climbing into the upper 80s.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
An upper ridge will expand over the area Wednesday night and
Thursday, then a zonal flow will persist into the weekend. Above
normal temperatures will prevail. A weak cold front could
approach during the weekend, potentially bringing scattered
showers and thunderstorms.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR conditions are expected to prevail at KCHS, KJZI, and KSAV
through 12Z Monday.

All sites will experience broken 3500-4000 ft ceilings for a
few hours this morning and early afternoon, before the sea
breeze passes inland, and is followed by some gusts of 15 or 20
kt in its wake.

An onshore flow might generate some MVFR ceilings late tonight.
But the higher probabilities are inland, so no mention in the
latest set of TAFs.

Extended Aviation Outlook: Prevailing VFR.

&&

.MARINE...
Today: High pressure centered across the western Atlantic will
extend across local waters, resulting in mainly quiet weather
conditions. Long fetch over the past few days will continue to
support seas around 6 ft across offshore Georgia waters, and
therefore a Small Craft Advisory until 6 PM. Otherwise, expect
winds/seas to remain below advisory criteria across nearshore
waters with seas as high as 3-5 ft early, subsiding to 2-4 ft by
late day. East-southeast winds should gust no higher than 10-15
kt across most waters, but could occasionally gust to 20 kt
across offshore Georgia waters where the gradient is slightly
stronger into the afternoon.

Tonight: The high shifts a little further south, but maintains
its hold on the coastal waters. The resulting gradient becomes
quite slackened, and once sea breeze influences wane in the
evening, SE winds will be only around 10 kt or less. Seas will
be 3 to 5 feet, highest on the Georgia waters beyond 20 nm
offshore.

Fairly quiet marine conditions expected Monday through Friday as
Atlantic high pressure remains in place. Sustained winds will
generally be no higher than 10-15 kt with seas no higher than 4
ft. A decent afternoon sea breeze is expected each day along the
coast, with occasional gustiness in Charleston Harbor.

Rip Currents: Onshore winds and small swells will lead to a
Moderate Risk of rip currents at all beaches today.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for AMZ374.

&&

$$

NEAR TERM...DPB
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...
MARINE...DPB