344
FXUS62 KCAE 241750
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
150 PM EDT Sat May 24 2025

.SYNOPSIS...
High pressure provides warm and dry conditions to begin the
Memorial Day weekend. Moisture returns overnight and Sunday
kicking off the start of an active weather pattern. Multiple
rounds of shortwaves and a stalled surface boundary will
support scattered to numerous showers and thunderstorms for much
of the long term.

&&

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

- Clouds increase towards evening with showers and perhaps a
thunderstorm or two moving late tonight.

Skies are mostly clear to partly cloudy this afternoon with the main
area of precip well off to our west across northwest GA.
Temperatures are below normal, generally in the upper 70s to around
80 degrees with dewpoints in the 40s. High pressure continue to
dominate through most of today with PW values generally around 1".
Expect increasing clouds particularly this evening as a shortwave
trough approaches from the west. Clouds thicken especially after
midnight, with showers moving in from west to east early Sunday
morning. There remains the potential for a thunderstorm or two as
well, but the overall severe threat is low. Cloud cover and
increasing rain chances will limit cooling tonight with
low temperatures only reaching the low to mid 60s.

&&

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

- An active weather pattern is forecast to begin on Sunday
- Wedge conditions begin to settle in on Monday and Monday night

Showers and isolated thunderstorms are expected to be ongoing
across the forecast area on Sunday morning. These are forecast
in in advance of a shortwave pushing southeastward within the
weak upper level flow, with warm advection & PWs >1.5" helping
sustain the precipitation. Expect some lull in rain but a
redevelopment of showers/storms again during the evening hours
as another shortwave approaches. This shortwave is also forecast
to help spark the development of a low pressure system off the
SC coastline by Sunday night, which should help to fully begin
ushering in wedge conditions on Monday. Highs on Sunday are
tricky and completely dependent on overall precip coverage and
duration into the afternoon. But because moisture increases
rapidly tonight, in addition to an increase in clouds, expect
that temps will be warmer to start Sunday and therefore a bit
more prone to rising if the sun peeks out.

Monday looks more like a day out of mid to late winter, from a
weather perspective that is. Aforementioned coastal low is
expected to help set up cold air damming conditions in the
Carolinas as northeasterly surface flow develops across the
region. Clouds are expected throughout the day, with well below
normal temperatures expected as a result. Overall precipitation
chances look lower through the day than on Sunday or again on
Tuesday (more on that momentarily) but some showers should be
around. Think that this is owing to some subsidence in the wake
of the departing shortwave & with weak shortwave ridging pushing
in ahead of Tuesday`s shortwave trough. So in general, Monday
looks cloudy and cool. Highs will only be in the upper 70s to
around 80F for most. Lows Monday night will likely be in the mid
60s with showers increasing by early Tuesday.

&&

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

- Well below normal temps expected in wedge conditions Tuesday
- High confidence in unsettled weather continuing through the
  end of the week

Unsettled weather continues to be the theme of next week.
Guidance is in good agreement that upper level flow will remain
generally weak and zonal in nature through Thursday night, with
repeat shortwave passing over a moisture rich environment. To
begin the period, cold air damming and wedge conditions are
expected across the entire area on Tuesday. Strong mid/upper
level convergence across the Mid-Atlantic is expected to foster
the setup and help it persist throughout Tuesday. Meanwhile, an
approaching shortwave trough is expected to yield strong
isentropic lift on the 295K-300K theta surfaces, favoring
widespread rainfall throughout the day on Tuesday. Forecast
highs continue to trend downward and still may not be low
enough; truly, forecast soundings from the NAM/GFS resemble more
mid/late February than late May!

Thereafter, the weather continues to look active and unsettled
through the end of the week. There remains some skepticism that
the wedge will clear out on Wednesday even with the shortwave
passing to our northeast. That could complicate the forecast,
specifically with respect to highs. But regardless, with
somewhat weak southwesterly flow through the period, shortwaves
are likely to spark daily showers and thunderstorms given PWs
remain in the 120-150% of normal range through Friday. It
continues to look like a deeper trough should dig into the
eastern CONUS by late next week, helping to upend the pattern a
bit. Highs should be near to slightly below normal given
expectation of clouds & storms.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR conditions will deteriorate tonight into Sunday. Partly cloudy
skies this afternoon with periods of mid to high level cloudiness.
SFC winds generally light, increasing to 5-10 knots from the W/NW
this afternoon. Clouds expected to thicken and gradually lower this
evening with ISOLD-SCT -SHRA/-TSRA developing from west to east
after 25/03z. Impacts at the terminals not expected until closer to
25/06z, then continuing through the rest of the valid period. MVFR
CIGS expected much of the day Sunday, with further restrictions
possible especially in/around the heavier SHRA/TSRA. Light winds
overnight becoming SLY Sunday morning at 6-10 kts.

EXTENDED
AVIATION OUTLOOK...Brief periodic restrictions become possible
through the middle of next week due to diurnal convection.

&&

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

&&

$$