Area Forecast Discussion
Issued by NWS Columbia, SC

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879
FXUS62 KCAE 220542
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
142 AM EDT Tue Sep 22 2026

.WHAT HAS CHANGED...
Temperatures trending cooler for Wednesday and Thursday.
Aviation discussion updated for 06z TAFs.

&&

.KEY MESSAGES...
- 1. Above average temperatures and chances for showers and
  storms this afternoon and evening.

- 2. Cooler conditions expected Wednesday onward, with periods
  of showers mainly Wednesday and Thursday.

&&

.DISCUSSION...
KEY MESSAGE 1: Above average temperatures and chances for
showers and storms this afternoon and evening.

A weak shortwave approaches the region today along a lingering
stationary boundary, continuing to draw moisture northward
across the CWA. This disturbance will lift northeastward off the
coast later today in response to an upper-level trough
progressing through the Midwest. Broader synoptic forcing will
yield higher coverage in Pops, as a surface front pushing
southward across the Midlands Tuesday night supports widely
scattered showers and storms, primarily during the late
afternoon and evening hours. A few severe storms are possible as
MUCAPE values approach 2000-3000 J/kg with PWATs of 1.7-2",
supporting a localized threat for wet microbursts and damaging
wind gusts within the strongest storms. However, weak mid-level
lapse rates and minimal effective shear will keep the overall
organized severe risk limited. Highs will again be in the 90s
for one last time (hopefully).

KEY MESSAGE 2: Cooler conditions expected Wednesday onward, with
periods of showers mainly Wednesday and Thursday.

Models are generally converging on high pressure over the
northeast pushing the wedge front through our forecast area
late Tuesday into Wednesday. The ongoing showers and cloud cover
Wednesday morning will likely limit daytime heating, especially
with cold advection occurring at the surface. There remains
some uncertainty regarding how far south the wedge front will
go, and it is expected to have a tight temperature gradient
setting up somewhere across the southern Midlands Wednesday
afternoon. All said, the temperature drop of 10 to 15+ degrees
between Tuesday and Wednesday will be very noticeable north of
the front. There will also be some breezy northeast winds
accompanying this airmass change. Blended guidance struggles in
these scenarios, so we have been using the NAM/GFS models to
better capture the expected temperatures late this week.

Additional cloud cover and precip suggests Thursday could be our
coolest day of the week for high temperatures, with most expected to
remain in the low to upper 70s. An upper trough will work to scour
out the wedge through some portion of the day, with drier Northwest
flow eventually moving in. Highs will rebound a bit closer to normal
as precip and cloud free conditions return Friday and into this
weekend. Highs will generally reach the upper 70s to low 80s, with
overnight lows in the upper 50s to low 60s. Overall, this should
provide our first real taste of fall with a refreshing change in
temperatures arriving just as astronomical autumn officially begins
later today!

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
Possible br/fg this morning. Scattered thunderstorms expected
in the afternoon. Ceiling restrictions beginning late it the taf
period.

We will be entering a period of a changing weather pattern
across the region beginning late in the taf period. A surface
front will begin to push southward, but will remain well north
of the area through the daytime and early portions of the
overnight hours Tuesday night. This means one more day of what
will amount to a repeat of the past several days. Some patchy
morning br/fg can not be ruled out this morning, especially the
usual fog prone sites of ags/ogb. For this afternoon, another
round of scattered showers and thunderstorms is expected to
develop, and have generally continued with the mention of
Prob30`s by mid-afternoon. Will also begin to add mention of
vcts for much of the afternoon, and eventually change over to
vcsh by 03z as activity begins to wind down. With the approach
of the surface front late tonight, guidance is showing ceiling
restrictions developing from north to south, generally starting
around 03z and later. Will begin bringing mvfr ceilings into the
central Midlands at 03z, but hold off in the CSRA until later at
this time.

As for winds, easterly winds will pick up around 7 kts after
15Z. Winds could begin turning more northeasterly late in the
taf period, then turn out of the north more than likely after
06z timeframe as the cold front pushes into the area.

EXTENDED AVIATION OUTLOOK...Widespread restrictions and higher
rain chances expected Wednesday through Thursday as wedge
conditions set up across the region. Drier conditions expected
beginning Friday.

&&

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

&&

$$

DISCUSSION...ND
AVIATION...73