Williston, South Carolina Weather Forecast Discussion

376
FXUS62 KCAE 281800
AFDCAE
Area Forecast Discussion
National Weather Service Columbia SC
200 PM EDT Sun Sep 28 2025
.SYNOPSIS...
Dry conditions expected during the day today, with shower
chances returning tonight as Tropical Storm Imelda approaches
the Southeast. Locally heavy rainfall remains possible to start
the week as the tropical cyclone continues moving northward.
High pressure then moves into the region, bringing cool and dry
conditions to the area.
&&
.NEAR TERM /THROUGH TONIGHT/...
Key message(s):
- Becoming partly to mostly sunny with near normal daytime
  temperatures, warmest in the CSRA.
- Shower chances return tonight as Tropical Storm Imelda moves
  north through The Bahamas.
Satellite imagery this afternoon shows lingering low clouds
across the Midlands with mostly sunny skies over the CSRA. There
are also some high-level clouds associated with Tropical
Storm Imelda streaming into the eastern half of the CWA. In
general, skies should become partly to mostly sunny through the
CWA this afternoon, allowing temperatures to warm into the upper
70s to lower 80s in the Midlands and the lower to mid 80s in
the CSRA where they will receive more sunshine. Expect
cloudiness to increase towards evening as Tropical Storm Imelda
moves further north through The Bahamas. A few showers and
perhaps a thunderstorm cannot be ruled out later today,
especially along and east of I-95. Rain chances will increase
during the overnight hours, particularly across the eastern half
of the FA. There remains some question on when the rain enters
the CWA and how far west rain gets before sunrise as there is
some uncertainty in how fast the cyclone moves northward.
Temperatures should fall into the mid to upper 60s by daybreak.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
Key message(s):
- Cloudy, cool, and rainy conditions expected as moisture
  increases northward from TS Imelda.
- Increasing confidence in less impacts associated with TS
  Imelda including less rainfall with totals expected between
  0.5-1.5 inches.
Guidance continues to trend more to a solution that results in
decreased chances of impacts in our area associated with TS
Imelda. The cyclone remains weak at this time but is still
forecast to drift northward through The Bahamas and become a
hurricane as it encounters more favorable conditions by Monday.
A significant plume of moisture with PWATs 150-175 percent of
normal is expected to move over the forecast area on Monday. The
combination of this anomalous moisture and increased low level
convergence should result in periods of moderate to heavy
showers moving through the area on Monday. Instability will be
limited but cannot totally rule out thunderstorms, though they
are expected to be isolated. Rainfall amounts have decreased a
bit but any rainfall will be beneficial at this point and the
highest amounts should favor the eastern portion of the forecast
area with amounts ranging from a tenth to half inch in the west
to around 1-1.5 inches in the east. The best rain chances
appear to be Monday through Monday night. Widespread clouds and
precipitation will also significantly limit daytime heating and
high temperatures are expected to be 5 to 10 degrees below
normal with highs in the 70s, although some locations may
struggle to get out of the 60s due to rainfall.
Latest ensemble guidance has trended stronger towards TS Imelda
lifting northward off the east coast of Florida and then taking
a right turn due to the influence of the much stronger Hurricane Humberto
approaching from the east and a strong surface high that builds
into New England and the Mid-Atlantic and ridges into the
Carolinas. Isolated to scattered showers will remain possible on
Tuesday but with cooler high pressure building in from the
north thunderstorms appear less likely and the highest rainfall
is generally expected to remain closer to the coast east of our
area. Temperatures will again be below normal with highs in the
70s. An increased pressure gradient should support breezy
conditions but no significant winds are expected with gusts
generally topping out around 25 to 30 mph.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Key message(s):
- Increasingly dry and cool conditions are expected through the
  end of the week.
The extended forecast period should feature generally fair
weather with below normal temperatures and a taste of Fall.
Guidance continues to be in agreement showing TS Imelda
shifting further to the east on Wednesday away from the region
as a reinforcing cold front pushes southward through the
forecast area Wednesday night. Decreasing moisture begins on
Wednesday as the deeper moisture shifts offshore in the wake of
Imelda and PWATs are forecast to fall back below normal (less
than an inch) Thursday through the end of the week with deep
northeasterly to northerly flow in place. Ensembles are showing
below normal temperatures at 850mb associated with the anomalous
high pressure riding down the east coast and below normal
temperatures are expected to continue through Saturday with
highs in the 70s and lows dropping into the 50s and 60s.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Due to sufficient low-level moisture this morning, ceiling
restrictions are anticipated to remain in effect for a few
terminals through 18Z. High resolution model soundings support
cigs rising with diurnal heating early this afternoon, above
3kft across the region; therefore VFR conditions will prevail.
Outflow from ongoing offshore convection could lead to isolated
shower activity south of CAE after 00Z this evening. With weak
forcing, thunderstorm development will likely be limited. PROB30
will cover spotty shower activity after 00Z Monday.
Expect an elevated probability of IFR cigs across the region
between 04Z to 08Z Monday. This is attributed to the ongoing
deep moisture and a consistent large-scale pattern.
EXTENDED AVIATION OUTLOOK...Tropical Storm Imelda will continue
to advance north across the Caribbean this evening and will
likely intensity over the next 24 hours. Confidence is right now
low to medium on potential rain bands associated with this
tropical system. Worse case scenario: Rain band impacts may
start to cause restrictions after 00Z Tuesday.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...None.
GA...None.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...99

NWS CAE Office Area Forecast Discussion