176
FXUS62 KCAE 132359
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
759 PM EDT Tue May 13 2025

.SYNOPSIS...
Unsettled weather continues with some shower and thunderstorm
chances through Wednesday. An isolated storm on the stronger
side cannot be ruled out but widespread severe weather is not
expected and any rainfall should tend to be lighter than what
was seen the past couple days. Conditions begin to dry out to
end the week, with much warmer temperatures expected.

&&

.NEAR TERM /UNTIL 7 AM WEDNESDAY MORNING/...
Key Message(s):

- Isolated showers and thunderstorms overnight

The upper low continues to lift northward through the TN Valley
into the southern OH Valley this evening with a warm front
situated north of our area across northern NC. Convection today
was much lower in coverage and generally weaker in nature as the
deeper moisture shifted northeastward away from the region.
Radar showing some lingering showers and isolated thunderstorms
across the CSRA and western Midlands and this activity should
continue lifting northeastward into the overnight hours and
continue to weaken with the loss of instability. Expect
intermittent cloud cover through the night in the form of mid
and high clouds rotating around the departing upper low. Despite
these clouds, there could be enough breaks with generally weak
boundary layer winds and dewpoints in the 60s to support some
patchy fog, especially across the southeastern part of the
forecast area. Temperatures should generally bottom out in the
mid 60s.

&&

.SHORT TERM /7 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
Key Message(s):

- Isolated to scattered showers and thunderstorms Wednesday,
  especially across the Pee Dee and eastern Midlands.

- Warmer and dry on Thursday.

Wednesday and Wednesday Night: The upper trough to our northwest
at the start of the day heads northeast in response to building
upper ridging moving in from the west. This timing is faster
than in previous model runs. With the best forcing moving away
earlier than anticipated, CAMs have decreased coverage across
our forecast area. PoPs have been lowered on Wednesday in
response to this, with the highest values across the Pee Dee
which will be closest to the best upper lift in the afternoon.
Convection is likely to peak in the early afternoon, with rain
chances decreasing from southwest to northeast Wednesday evening
and into the overnight hours. The SPC has also made changes to
their Day 2 SWO, moving the Marginal (1/5) severe risk further
northeast but still across the Pee Dee and eastern Midlands.
Daytime temperatures should be similar to today with forecast
highs in the upper 70s to lower 80s, falling into the mid-60s at
night.

Thursday and Thursday Night: Upper ridging continues its
eastward movement on Thursday, while surface high pressure
strengthens in the eastern Gulf. The ridging should create
enough subsidence to prevent convective development, though with
PWATs around 1.5 inches, scattered cumulus will likely develop
in the afternoon. Daytime temperatures will be warmer with near
to above normal values expected. It will likely be balmy outside
during peak heating with forecast dewpoints in the upper 60s and
heat index values around 90 degrees.

&&

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

- Hot and humid conditions likely Friday, continuing into the
  upcoming weekend. Heat index values could approach 100 degrees
 during peak heating on Friday.

- Diurnally driven shower and thunderstorms chances each day.

Axis of upper ridge will be in our vicinity at the start of the
extended, flattening out in response to trough passing along
the US-Canadian border through Sunday. This should result in
above normal temperatures across our forecast area through the
period. Friday currently appears to be the hottest day of the
the long term and will combine with high dewpoints to create
heat index values around 100 degrees during peak heating. This
will be the first period of summer-like conditions in our area
this year, therefore caution should be exercised should these
conditions manifest and you have outdoor plans Friday afternoon.
A cold front is expected to move into our FA Saturday night,
potentially stalling near/over the region. This boundary could
serve as a lifting mechanism for daily shower and thunderstorm
chances. Uncertainty is higher than usual, therefore PoPs are
generally at or below 20 percent through the extended.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Generally VFR conditions expected for all terminals through the
TAF period.

Similar pattern to the last few days continues with a slow
moving low pressure still driving some scattered thunderstorms-
showers across the area. They are last widespread than the last
few days and are not expected to have major TAF impacts; only
mention is VCSH at AGS and DNL through 03z. We could see
another batch of showers very late tonight into Wednesday
morning, but confidence is too low for any mention yet. Cigs and
vsby should remain VFR otherwise, with some low end potential
for fog Wednesday. Winds and some mid-level cloud cover should
generally limit fog-stratus but can`t rule out some MVFR cigs-
vsby. AGS and OGB may see their typical MIFG overnight and
Wednesday, but the setup is not as favorable as the last couple
mornings.

Additionally scattered showers and storms likely Wednesday but
coverage should be low compared to the last few days.

EXTENDED AVIATION OUTLOOK...Rain chances finally decrease late
Wednesday with a return to fairly typical summer cu and an
isolated afternoon storm Thursday and Friday.

&&

.HYDROLOGY...
Recent heavy rainfall has produced widespread amounts of 3
inches over the past 5 days, with amounts of up to 6-7 inches in
some locations. As a result, river flooding along the Congaree
River from Columbia to Gadsen is expected. In addition, Lake
Greenwood increased their releases, cause the Saluda River at
Chappells to go into flooding today as well. River flooding is
also possible along the Edisto River at Orangeburg, PeeDee River
at Cheraw, and the Wateree River just below the Lake Wateree
Dam. Will continue to monitor these locations for the need of
additional flood warnings.

&&

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

&&

$$