310
FXUS62 KCAE 251743
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
143 PM EDT Wed Jun 25 2025

.SYNOPSIS...
Hot and humid conditions, with dangerous heat index values, are
expected again today under the continued influence of a strong
upper ridge. Numerous showers and thunderstorms expected this
afternoon and evening as an upper trough moves west toward the
coast. Potential for a significant severe weather event with
damaging to destructive winds and large hail possible. A few
stronger thunderstorms are possible again Thursday and Friday as
the upper low lingers near the forecast area. Typical
summertime weather expected this weekend and into early next
week with near to slightly above normal temperatures and daily
shower and thunderstorm chances.

&&

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

- Dangerous heat expected to continue today.
- Numerous showers and thunderstorms this afternoon and evening.
- Significant severe weather threat possible with damaging to
  destructive winds and large hail the primary hazards.

A potentially significant severe weather event is expected to
unfold this afternoon across the Midlands and CSRA. Before we
get to that, the heat is oppressive across the region this
morning. We are already in the low-mid 90s as of 1045a at all
sites, with dewpoints in the mid to upper 70s. Heat index
values are likely to exceed 105F by early afternoon, with some
values as high as 110F-112F. Please exercise caution if you`re
participating in outdoor activities today.

To put it bluntly: today`s severe weather setup is very unique
and potentially dangerous. Upstream 12z soundings at Wilmington,
NC and Charleston, SC reveal an environment that can only be
described as extreme, with observed SBCAPE and MLCAPE values of
3000-4000 j/kg, TEI values of 34-40, and cloud layer shear of
45-50 knots. Peak mid-level lapse rates are absurd, running
around 9-9.5C/km. DCAPE values of 1200-1400 j/kg are expected as
we mix and develop inverted V soundings in the low-levels
beneath dry and cool air aloft. Not totally sure any other
adjective fully sums up the setup other than extreme. In
addition to all of this, the event is forecast to be well forced
as a strong upper low pushes towards the region. An
anticyclonically curved upper level jet streak is noted across
northern/western NC in GOES Derived Mean Wind products, peaking
at 50-60 knots in strength. We are placed in the right-exit
region of this jet streak. which is favorable with this
orientation and translation of this particular jet streak. So
convection is expected to begin as early as 1p, with most CAMS
running around a 2p-3p initiation time.

Wind damage is the primary threat today, with SBCAPE near 5000
j/kg, DCAPE near 1400 j/kg, and inverted V low-level soundings
yielding widespread damaging wind gusts. The strongest storms
have the potential to yield 80 mph winds in isolated spots.
However, the 12z soundings suggest there could be a robust hail
threat with the initial convection. Cloud layer shear in the 50
knot range is certainly sufficient for severe hail. Add in the
kind of thermodynamics that are in place and the hail threat
grows. Ultimately, if you are under a Severe Thunderstorm
Warning today, please take it seriously and take shelter
indoors. These storms will be capable of significant severe
weather hazards including copious lightning, damaging winds, and
large hail.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Key Message(s):

- Still quite hot with a chance of mainly afternoon and evening
  showers and thunderstorms.
- A few thunderstorms could be strong to severe as the upper low
  lingers over Georgia.

Little change in the forecast thinking for the short term
period. Upper low will be centered over Florida at the start of
the period, moving slowly northwest into Georgia while
weakening through the period. This feature will break down the
upper ridge over our forecast area allowing temperatures to
return to seasonal levels. While conditions do not appear as
favorable for strong to severe thunderstorms on Thursday, the
upper low will likely aid in convective development, which
should be focused along the sea breeze and any lingering
boundaries from today`s convection. Modeled soundings still show
an inverted-V, though CAPE values are about as half as today.
Regardless, this seems adequate to support the wind driven
Marginal (1/5) risk for severe weather across our CWA in the Day
2 SPC SWO. Much of the forecast area is also in a Marginal risk
on Day 3 but the severe risk should diminish with each day as
the upper low continues to weaken. Temperatures will be near to
slightly above normal. Peak heat index values should remain
below criteria but will remain elevated in the 95 to 105 degree
range.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Key Message(s):
- Typical summertime pattern with near to slightly above normal
  temperatures and daily chances for showers and thunderstorms.

Little change in the forecast thinking for the long term period.
High pressure near Bermuda will maintain a summertime warm and
humid air mass over the FA during much of the extended. Expect
near to slightly above normal temperatures in addition to
scattered afternoon and evening showers and thunderstorms. A
trough may take shape over the Great Lakes region early next
week which could serve to enhance the risk of showers and
thunderstorms, especially if a cold front can make it into the
region. NBM guidance shows an uptick in PoP towards the end of
the long term. Opted to cap PoPs in the Chance category for now.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Cumulus is beginning to develop this afternoon as strong to
extreme instability develops across the forecast area.
Thunderstorms are expected to erupt after 18z and begin to
impact the area TAFs sometime this afternoon. Confidence is
relatively low on timing but highish on overall coverage and
impacts. Thunderstorms are forecast to be severe this afternoon,
but impacts at each terminal will depend on the location of said
thunderstorms. TEMPO group for all sites from 22z to 02z to
account for the convection but that is a loose timeframe and
will likely adjust as convection fires up. Later tonight, fog
and stratus is certainly possible at area TAF sites but unlikely
to be well forecast right now and dependent on who gets the most
rainfall. AGS/OGB are the typical fog sites so have included a
predominant MVFR fog group there after 08z tonight. More
showers/storms are possible on Thursday afternoon and evening.

EXTENDED AVIATION OUTLOOK...Widespread thunderstorms also
possible Thursday afternoon and evening. Fog will be possible
Thursday night, especially in locations that receive heavy rain.
Diurnally driven scattered thunderstorms each afternoon through
the weekend.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...Heat Advisory until 8 PM EDT this evening for SCZ016-018-
     020>022-025>031-035-037-038-041-115-116-135>137.
GA...Heat Advisory until 8 PM EDT this evening for GAZ040-063>065-
     077.

&&

$$

SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...