911
FXUS62 KCAE 221747
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
147 PM EDT Sun Sep 22 2024

.SYNOPSIS...
High pressure building over the SE US will keep warm conditions
over the Southeast into the first half of the work week.
Multiple shortwaves moving overhead bring at least daily slight
chances for precipitation through much of the week. Confidence
is low in the forecast beyond midweek as uncertainty remains
high with the evolution of an upper trough moving toward the
region and the potential for tropical development in the Gulf.

&&

.NEAR TERM /THROUGH TONIGHT/...
Key Message(s):

- Upper ridge persists with above normal temperatures.
- Isolated afternoon showers or storms over southeastern
  Midlands and CSRA.

This afternoon: Hot temperatures persist underneath the upper
ridge axis, with highs still on track to reach the low to middle
90s.

Tonight: Weak surface trough may be able to trigger an isolated
shower or storm across the eastern Midlands and CSRA early this
evening, generally in an area with slightly higher pwat values.
Any activity that develops would dissipate by 02z tonight, with
dry conditions then expected the remainder of the night. Winds
turning light overnight. Lows tonight remaining on the milder
side, bottoming out generally around 70 degrees.

&&

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

- Upper ridge continues to bring above average temps.
- Afternoon and evening precipitation is possible each day,
  mainly north.

Upper ridging is expected to be over the area as surface high
pressure is filtered into the region from the Northeast to
start the short term period. Meanwhile, an upper trough is
forecast to continue developing over the Upper Midwest. All of
these features slide eastward over the short term period.
Multiple shortwaves are forecast to ride around the periphery of
the ridge as it passes overhead, bringing chances for
precipitation to the northern half of the forecast area each
afternoon and evening. Also, the upper trough is anticipated to
dig southward and assist in developing a surface frontal
boundary, resulting in southwest flow locally. The southwest
flow will likely lead to increased moisture to the region ahead
of the frontal boundary, bringing slightly higher chances for
precipitation on Tuesday. Due to the ridging, temperatures are
expected to remain on the warm side, with highs in the mid 80s
north to lower 90s south each day. Overnight lows remain warm as
well, with lows around 70.

&&

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

- Chances for precipitation increase in the long term despite
  forecast uncertainty.


Uncertainty remains pretty high in the long term, leading to a lower
confidence forecast. The two main features causing uncertainty are
the aforementioned upper trough and the potential for tropical
development in the Gulf of Mexico. For the trough, some guidance
shows the trough will continue to most eastward as an open trough,
while others indicate it will close off. For the tropical
development, the National Hurricane Center is not expecting
development in the next 48 hours, but has increased the
probability of development to 70% within the next 7 days. So,
confidence is increasing the some tropical system will develop
in the Gulf, but where it goes and how strong it gets is where
the uncertainty comes in. Assuming something does form, the
strength and track of it will be partly dependent on what
happens with the upper trough. Regardless of what happens, daily
chances for precipitation continue through the forecast period.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Outside of KAGS, generally VFR conditions anticipated through
the TAF period. KAGS may see usual mvfr/ifr visibilities
overnight near the river.

Skies mostly sunny this afternoon with satellite and visual
observations showing the development of a few afternoon cu. Weak
surface trough moving through the area, may combine with
slightly better moisture and instability across the eastern
Midlands and Central CSRA areas to develop an isolated shower
during our peak heating hours this afternoon. Coverage would
appear to remain rather limited based on latest models, and am
inclined to keep mention of any activity out of any tafs due to
the low confidence of a terminal being impacted. Conditions will
remain vfr through the period at all taf locations except at
KAGS. In that locations, the usual overnight development of
mvfr/ifr visibilities will remain possible after 07z lasting
through around 12z. Otherwise vfr at that location. Winds
mostly out of the westerly around 5 to 6 knots through the
afternoon, then light and variable overnight into Monday.

EXTENDED AVIATION OUTLOOK...There are no significant concerns
for restrictions at this time.

&&

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

&&

$$