816
FXUS62 KCHS 192000
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
400 PM EDT Sat Oct 19 2024

.SYNOPSIS...
Dry high pressure will prevail through late next week.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
An expansive 594 dm ridge centered over the northern Gulf of
Mexico will shift west over the Mississippi River Valley
tonight. At the surface, high pressure will remain over the mid-
Appalachians through tonight. Forecast soundings indicate a
very dry thermal profile, supporting rain-free conditions
across the CWA. Outside of some thin cirrus passing over the
area this evening, clear skies are expected. Good radiational
conditions, mainly inland, will lead to another chilly night.
Elevated winds along the coast will keep temperatures from
radiating as cool as the interior counties. The forecast
features min temps in the mid to upper 40s inland and low to mid
50s along the coastal communities.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
A deep ridge of high pressure, centered over the mid Atlantic
and southeast states, will gradually weaken and shift southward
through the period as strong upper shortwave trough moves into
the OH River Valley by Tuesday. Temperatures will continue near
normal Sunday and Monday with highs in the mid to upper 70s and
lows in the upper 40s well inland and lower to mid 50s closer to
the coast. By Tuesday, highs moderating to slightly above
normal, around 80 to the lower 80s. Dry conditions with no
precipitation expected over land. Surface dewpoints still very
comfortable in the mid 40s to mid 50s Sunday and Monday,
modifying slightly later Monday and Tuesday, reaching the lower
60s to mid 60s, except mid to upper 50s well inland.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A continuation of a dry pattern is expected to persist through this
period. The deep layer ridge is shown by global models to erode/push
southeast of the area as an upper level trough moves through the OH
River Valley and then across New England by later in the week.
Another cold front may approach the region on Thursday, but deep
layer moisture is lacking, which means the front will likely come
through with little/no precipitation. Models differ in timing of the
cold front, but consensus solution would have it pushing through
Thursday afternoon/evening. High pressure looks to build back from
the northwest Thursday night and Friday. Temperatures expected to be
3 to 5 degrees above normal through Thursday, then back to near
normal Friday, behind the next cold front.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
VFR conditions with steady northerly winds will continue at the
terminals through 18z Sunday.

Extended Aviation Outlook: VFR conditions expected to prevail
through much of the week.

&&

.MARINE...
Tonight: The surface pattern will be dominated by high pressure
centered over the mid-Appalachians and low pressure near
Bermuda and across the southern Caribbean. This will result in
NE winds 15 to 20 kt. Frequent gusts around 25 kt will continue
tonight across the Georgia waters. Seas are forecast to range
between 3 to 5 ft across the SC waters, and 4 to 8 ft across the
GA waters. Small Craft Advisories will continue for both the
nearshore (0-20nm) and outer Georgia waters (20-60 nm). However,
SCA conditions are marginal across the nearshore waters
potentially allowing for an early expiration later this evening
or tonight.

Sunday through Thursday: A ridge of high pressure is expected to
remain north and east of the waters through at least Tuesday.
This will continue long fetch northeast winds of 15 to 20 knots
with seas 4 to 6 feet within 20 nm and 5 to 8 feet offshore GA
waters. Expect SCA conditions, for seas, to continue over AMZ354
and AMZ374 for the next few days. The pressure gradient starts
to relax some by Tuesday night and Wednesday with lighter
northeast winds and decreasing seas. By Thursday, another cold
front is expected to approach the waters, with light north-
northwest to variable winds ahead of the front. In general, very
low chances for any precipitation through the period, but
cannot rule out isolated showers, especially closer the Gulf
Stream well offshore Sunday night through Monday night/early
Tuesday.

Rip Currents: Came up with a high end low risk, especially for the
GA coast given long fetch northeast winds of 10-15 knots and
background seas/swells of 1-2 feet at a period of 10-12 seconds.
Will let next shift take another look to see if it needs to be
bumped up to a Moderate, especially for the GA coast.

&&

.TIDES/COASTAL FLOODING...
Minor coastal flooding likely to continue along the SC coast during
the morning high tides through early next week due to the positive
anomalies from moderate NE flow.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...Small Craft Advisory until midnight EDT Monday night for
     AMZ354.
     Small Craft Advisory until 6 AM EDT Wednesday for AMZ374.

&&

$$

NEAR TERM...BRM
SHORT TERM...RFM
LONG TERM...RFM
AVIATION...BRM/RFM
MARINE...BRM/RFM