854
FXUS62 KCHS 291045
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
645 AM EDT Mon Apr 29 2024

.SYNOPSIS...
High pressure will prevail through much of the week. A weak
disturbance will move through Tuesday and Wednesday, then a
weak cold front will stall in the vicinity this weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Temperatures got down to 50F degrees at Walterboro and Ravenel,
with 51-53F degrees at numerous other sites. Sylvania was the
coldest though at 49F degrees.

Today: A broad and amplified ridge will persist aloft, with 500
mb heights as high as 5820-5830 meters. At the surface, an
elongated rise extends across the immediate counties, which
continues to shunt any frontal systems far off to the north and
west. Strong insolation throughout the day, along with 850 mb
temperatures rising to 14-15C, will result in max temperatures
very close to climo. As the synoptic flow veers to the south-
southeast we stayed close to the low level thickness forecast
blended with the MOS consensus, NBM and NBM50%. This produces
highs 80-84F degrees, several degrees cooler along the beaches.

Tonight: While the Atlantic high at the surface e remains in
control, the ridge aloft is nudged east in advance of a short
wave that is initially near the ArkLaTex and reaches near the
southern Appalachians late. There might be a few showers out
near the Gulf Stream, but nothing over land areas. We`ll be
able to radiate decently early on,under mainly clear skies and
light winds. But an increase in cirrus clouds with the short
wave will arrive from the west late, and that along with the
formation of some late night stratus, will prevent us from
getting as cool as Monday morning. Lows will be mainly upper 50s
and lower 60s, with middle 60s closer to the shore, and in the
metro areas of Charleston, North Charleston, and Savannah. There
remains enough boundary layer moisture to potentially produce
some late night fog well inland, especially if stratus does
occur.

&&

.SHORT TERM /TUESDAY THROUGH THURSDAY/...
A pronounced upper shortwave will slowly move through the area
Tuesday into Wednesday. A decent slug of moisture will accompany
the feature with PWATs around 1.25". Surface-based CAPEs will be
500-1000 J/kg Tuesday and Wednesday. Isolated to scattered
showers and tstms possible Tuesday and Tuesday night. The
shortwave is expected to move off the coast by late Wednesday
morning, however some guidance hints at a weak surface trough
lingering over southern SC into Wednesday afternoon. There could
be just enough moisture and convergence to support a few
showers or tstms Wednesday afternoon, especially across the
northern half of the area. Tuesday highs will be in the mid 80s
and Wednesday will be mid/upper 80s.

Deep layered ridging will occur on Thursday, yielding a dry and
toasty day with highs in the upper 80s to lower 90s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
The upper ridge will persist into Friday before pushing off the
coast over the weekend. Then, a quasi-zonal flow will develop
with a series of shortwaves rippling through. Greater coverage
of mainly diurnal convection expected during this period. Above
normal temps will persist with highs in the mid/upper 80s.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
KCHS/KJZI/KSAV: VFR through 12Z Tuesday. Any low stratus and/or
patchy fog late tonight looks to occur well inland from all
sites.

Extended Aviation Outlook: Prevailing VFR.

&&

.MARINE...
Today and tonight: Atlantic high pressure will be firmly in
control, and even with a subtle boost from the sea breeze, SE
winds will be no more than 10 or 15 kt. Seas just 2-4 feet.

Atlantic high pressure will remain the dominant feature Tuesday
through Saturday, with winds generally no higher than 10-15 kt
and seas 2-4 ft. A moderate coastal sea breeze will develop each
afternoon.

Rip Currents: A small swell every 9 or 10 seconds, and
continued onshore winds, will result in a Moderate Risk of rip
currents at all beaches today.

&&

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

&&

$$

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