Sumter, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

801
FXUS62 KCAE 220615
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
115 AM EST Sun Dec 22 2024

.SYNOPSIS...
Strong high pressure sliding to our north brings continued chilly
conditions into Monday. Both daytime highs and overnight lows are
expected to be below normal. More seasonal temperatures follow, with
increasing chances for rain as an active pattern moves into the area.

&&

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

- High pressure builds and chilly conditions prevail.

With an upper trough continuing to push through the area and
northwest flow developing behind it, deep layer dry air is
pushing over the forecast area with satellite derived PWATs
around a quarter of an inch. As the surface high, which remains
over the Great Lakes, builds southeast towards the Mid-Atlantic,
winds will increase a bit out of the north overnight. This will
prevent ideal radiational cooling overnight but still cold
advection will promote lows dropping into the mid to upper 20s.

&&

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

- Cold and dry conditions likely through Monday afternoon.

- A coastal low may bring the threat of precipitation Monday
  night, especially across the eastern Midlands.

Strong high pressure centered in Ontario at the start of the
short term will move east, passing offshore on Monday. This will
maintain a cold, dry air mass over the FA during much of the
period. Sunday is expected to be the colder of the two days with
well below temperatures likely during the daytime and overnight
periods. While confidence in subfreezing temperatures Sunday
night remains high, a Cold Weather Advisory does not appear to
be needed as guidance has once again trended a few degrees
warmer.

One concern towards the end of the period comes in the form of
a possible coastal low spreading precipitation into our eastern
FA late Monday night. While surface temperatures may be near the
freezing mark as precipitation is moving in, modeled soundings
show plenty of warm air aloft, so snow appears unlikely at this
time. However, will need to monitor trends for a brief period
of freezing rain during the pre-dawn hours of Christmas Eve.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Key Message(s):

- Any precipitation should end Tuesday morning, as the coastal
  low pulls away.

- Near normal temperatures return to the region, gradually
  warming late in the week.

- Rain chances increase but confidence remains low.

The period opens with the aforementioned coastal low passing to
our east. Current thinking is that any precipitation should
come to an end Tuesday morning, followed by partial clearing.
The remainder of the extended has increased uncertainty as a
series of disturbances move through the region. There will be a
chance of rain Wednesday through Friday, with the highest
probability on Wednesday night as a shortwave passes through.
Temperatures during the mid-week period will be warmer, with
near normal forecast highs Tuesday through Thursday, warming
gradually towards the end of the week.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
High confidence VFR conditions expected through the TAF period.

SKC. The dry air mass and elevated winds should prevent any
fog/stratus concerns this morning. Winds will be from the northeast
around 4 to 7 knots most of the night, then increase slightly to 6
to 10 knots by mid morning through the afternoon hours. Light and
variable winds are expected tonight into Monday morning.

EXTENDED AVIATION OUTLOOK...There is potential for a few rain
showers and associated restrictions Monday night through the end of
the week.

&&

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

&&

$$