803
FXUS62 KCAE 151834
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
234 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 /THROUGH TONIGHT/...
Key Message(s):

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

High pressure and upper ridge remain stationed over the
northeast, while an off shore low is continuing to develop. As a
result, a fairly tight pressure gradient across the area is
causing breezy northeast winds this afternoon, with gusts in the
20 to 30 mph range. After sunset, winds are likely to lower
some, but remain breezy due to the pressure gradient. A few
showers are possible in the eastern portions this afternoon and
evening. Rain chances are then anticipated to gradually increase
overnight from the east to west as the off shore low drifts
closer to the area. Rain chances are highest for the northern
and eastern portions of the forecast area.

&&

.SHORT TERM /MONDAY 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 /17Z SUNDAY THROUGH THURSDAY/...
VFR conditions into tonight before transitioning to MVFR.

Breezy northeast winds gusting to 20-25 kts are expected to
continue into the overnight, but easing somewhat after sunset.
The winds are expected to increase again after daybreak and
shift more northerly. Broken VFR clouds continue through about
05z-07z, then become MVFR for much of the rest of the TAF
period. Some showers are expected to move into the area and
approach the CAE/CUB/OGB terminals with IFR cigs possible late
in the TAF period.


EXTENDED AVIATION OUTLOOK...Scattered showers with possible
restrictions at times through the day Monday as moisture pools
over the area along a front and low pressure near the southeast
coast.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...None.
GA...None.

&&

$$