Area Forecast Discussion
Issued by NWS Columbia, SC

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178
FXUS62 KCAE 180020
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
820 PM EDT Fri Oct 17 2025

.SYNOPSIS...
Dry and cooler conditions are expected today with temperatures
warming up on Saturday ahead of the next storm system. A cold
front will cross the FA on Sunday bringing breezy winds and the
next chance for showers and maybe a storm or two. Dry weather
is likely to follow next week.

&&

.NEAR TERM /UNTIL 8 AM SATURDAY MORNING/...
Key message(s):

- None

High pressure continues to be the dominant feature over the
area with some high clouds passing over the area. Weak upper
ridging moving into area will allow temperatures to moderate a
bit tonight with lows in the low to mid 50s. Once again some
patchy river fog will be possible near sunrise but with
crossover temperatures lower, widespread fog is not expected.

&&

.SHORT TERM /8 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
Key message(s):

- Dry weather continues Saturday with dry weather.

- A cold front moves through Sunday with a chance of showers
  and thunderstorms along with breezy winds.

Saturday and Saturday Night: The upper ridge moves overhead
with high pressure hanging on during the day Saturday before
both features get ushered off shore with a potent trough digging
into the Midwest and down into the Southern Plains. This will
help turn low level flow out of the southwest during the day,
allowing moisture to slowly increase and bring afternoon
temperatures up into the upper 70s to low 80s. A surface cold
front associated with the upper trough creeps closer overnight,
but is expected to remain west of the region and thus dry
weather likely continues, though cloud cover may increase toward
Sunday morning. Overnight lows in the mid to upper 50s are
expected.

Sunday and Sunday Night: 12z model guidance has given a bit
more confidence in the progression of the potent upper trough
and surface cold front Sunday, but some timing differences
remain. In general, longer duration CAMs, and the deterministic
RAP/NAM/GFS/ECMWF, show the cold front in the western
Appalachians between 12z and 15z with a line of convection ahead
of it, likely also forced by a shortwave ahead of the main
trough axis. How this convection progresses is a bit more
uncertain, with discrepancies between guidance on the amount of
moisture that pools ahead of the front, and the overall
propagation speed of the convection. Majority of guidance does
show a general weakening trend in the line as it moves across
GA, likely due to a lack of instability from overspreading
debris clouds and a 90+ knot upper jet streak pulling away north
of the region. The ECMWF is the most aggressive in terms of
moisture ahead of the front with a broad tongue of PWAT`s
between 1.70-1.80" while the GFS is a bit more conservative. In
terms of timing, the ECMWF/NAM are on the slower side, with
weakly organized convection reaching the western FA between
18-21z while the GFS/RRFS/RAP are a bit quicker and less
organized, with activity moving in between 15-18z.

Overall, very little instability is forecast ahead of the front
(MUCAPE under 500 J/kg) but deep layer shear is expected to be
on the order of 40-50 kts with generous low level shear as
well. With the expected limited instability and timing
differences, confidence in thunderstorm activity across the FA
is on the lower side with the best chance being in the western
FA at this time and the remainder of area looking at isolated
to scattered showers before the front clears by the overnight
hours. Some breezy winds will be possible ahead of the front
also with gusts to 20-25 mph expected at this time. Dry
conditions likely move in behind the front overnight with lows
back into the upper 40s.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Key message(s):

- Dry weather likely returns for the extended period.

Not much change in the extended period forecast as cool and very
dry air filters in with high pressure for the early week
(PWAT`s likely under 0.50"), leading to temperatures that are
initially below average Monday, then near average on Tuesday.
Another cold front is expected to pass late Tuesday and into
Wednesday, but the very dry airmass should preclude any rain.
This will bring another push of cooler air with just below
average temperatures Wednesday and Thursday, though dry
conditions likely prevail as surface high pressure builds back
in, possibly continuing into the the end of the week. With this
cool and very dry air across the region, multiple nights next
week of near ideal radiational cooling conditions are expected
where chilly lows into the 40s will be possible.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Apart from fog at AGS and OGB, VFR conditions expected

High pressure remains in place over the terminals with high
clouds overhead. Once again, widespread fog is not expected
tonight, however, fog prone AGS and OGB will likely experience
periods of visibility restrictions after midnight. High clouds
remain thin and winds are light and variable so while low level
moisture is lacking overall, OGB and AGS proximity to rivers
will support patchy fog. Any visibility restrictions will
dissipate shortly after sunrise, with winds increasing out of
the southwest between 5 and 10 knots and decreasing high clouds.

EXTENDED AVIATION OUTLOOK...The next chance for widespread
restrictions will be Sunday morning ahead of a cold front which
will move across the Southeast.

&&

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

&&

$$