577
FXUS62 KCAE 160016
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
816 PM EDT Sun Sep 15 2024

.SYNOPSIS...
High pressure extending into the region from the north will
weaken as a low pressure area offshore moves toward the Carolina
coast tonight into Monday. Breezy conditions and scattered to
numerous showers are expected through Monday night. Moisture will
remain high across the area through mid week with scattered
mainly diurnally driven showers and thunderstorms. Lower chance
of rain late week as drier air moves into the area. Temperatures
cooler than normal early in the week then expect a warming
trend.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Key Message(s):

- Breezy conditions continue through tonight.
- Rain chances gradually increase overnight, mainly for the
  eastern and northern portions of the forecast area.

Well, PTC8 has developed off the coast of SC and is influencing
our weather currently and through the near term period. Though
there is a change in the status of this area of low pressure,
our expected impacts won`t change much from the previous
forecast. Isolated showers are pushing through the area right
now, with a more solid area of rain shifting westward towards
Clarendon/Lee/Sumter counties over the next several hours.
Clouds are expected to really be thick across the eastern FA,
with coverage decreasing westward. Additionally, strong surface
high pressure remains in place to our north. With PTC8
developing and the pressure gradient continuing to intensify
expect gusty winds to continue through much of the night
tonight. A Lake Wind Advisory has been issued for the eastern
half of the area beginning at 2am to account for this as winds
are expected to gust 35-45 mph on area lakes tonight and into
Monday. Expect lows tonight in the upper 60s and lower 70s.


&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
Key Message(s):

- Locally heavy rain possible in the Pee Dee Region Monday and
  Monday night
- Gusty north winds 20 to 30 mph Monday.

Monday and Monday night...Low pressure, currently offshore of
SC along a stalled frontal boundary is expected to move onshore
sometime Monday. Expect 18z models to have a better handle on
the overall development/track with data from NHC reconnaissance
mission. Notice large spread in track guidance/timing of low
moving onshore, but ensembles appear to favor north coast SC and
coastal NC. Although steering flow weak, latest water vapor
shows a robust short wave over southeast GA/SC, which should
nudge coastal low to the north. Model guidance in general
suggest a weak low pressure system with some tropical
characteristics. As the low moves toward the coast tonight,
moisture flux/warm advection will increase primarily across the
north coast SC/Pee Dee and eastern North Carolina. Precipitable
water will increase likely to values above 2.00-2.25 inches in
the Pee Dee. So locally heavy rain possible in that region with
up to 3.00 inches. Elsewhere, qpf amounts expected to much
lower. Continued a large range in pops from slight chance/chance
in the CSRA, to likely in the Pee Dee. Possible sharp
precipitation gradient across the area. Strong pressure gradient
across the area although ridge to the north will be weakening
as the low moves toward the coast, but expect gusty north winds
Monday to around 30 mph possible, especially in the morning to
midday. Temperatures will be cooler in the north Midlands with
highs mainly in the mid 70s. Near 80 degrees in the CSRA where
showers will be more limited. Stayed near the NBM mean. Lows in
the low to mid 60s with showers lifting to the north.

Tuesday and Tuesday night...Moisture could linger across the
region for Tuesday as the low pulls away from the forecast area.
A few showers will be possible but overall rain chances are
lower as the deepest moisture shifts north.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Key Message(s):

- Drier weather expected for mid-week
- Forecast uncertainty increases for late week

As a surface low moves north of the forecast area by mid-week,
relatively dry air is expected to wrap around the system and
move into the forecast area. However, GEFS appears to be more
moist than ECMWF/GEPS ensembles through the week. Uncertainty
with regards to temps/precip. Appears blocking pattern aloft
may set up with upper low remaining over the southeastern
States, leading to cooler temps and higher chance of rain each
day. Kept low pops through the period with mainly widely
scattered diurnally driven convection with overall weak forcing.
Temps near the NBM mean with warmest temps/above normal
Thursday, otherwise seasonal values.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
VFR conditions expected through around midnight before
transitioning to MVFR as low level stratus clouds return.

Breezy northeast winds persist with the increased pressure
gradient between the surface high to our north and the
developing potential tropical storm offshore which NHC has
begun issuing advisories on. Winds around 10 to 12 knots with
gusts to 20 knots expected overnight before increasing further Some
isolated showers across the Midlands this evening may impact
CAE/CUB so including VCSH for a few hours there, otherwise the
terminals are expected to remain rain free overnight. Expect
cigs to remain in the MVFR range through the day Monday with
possible IFR cigs during the afternoon as the low off shore
moves inland across northeast SC toward the Charlotte Metro
area. CAE/CUB could see some vsby restrictions in rain so
included a tempo group for that although there is some
uncertainty in the exact track and where the sharp gradient in
rain ends up.

EXTENDED AVIATION OUTLOOK...Scattered showers with possible
restrictions at times through Monday night with low pressure
moving across the Carolinas.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...Lake Wind Advisory from 2 AM Monday to 2 AM EDT Tuesday for
     SCZ016-020>022-027>029-031-037-038-115-116-135>137.
GA...None.

&&

$$