Area Forecast Discussion
Issued by NWS Columbia, SC

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967
FXUS62 KCAE 081621
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
1221 PM EDT Tue Jul 8 2025

.SYNOPSIS...
Temperatures remain above normal today and tomorrow with
diurnally driven showers and thunderstorms. Some decrease in
high temperatures is possible later in the week as weak upper
troughing moves in from the west while rain chances increase
slightly.

&&

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

- Hot with scattered thunderstorms expected this afternoon
  across the area, with some isolated damaging winds possible.

Very hot and unsettled conditions expected this afternoon as above
average heights and ridging aloft remains in place. A weak thermal
lee of the Appalachians surface trough will linger across the
Upstate of SC this afternoon and the boundary of this will likely
act as the trigger for convection in the afternoon; HREF instability
fields depict a notable CAPE gradient across the Midlands by 18z.
This trough is evident in the overnight moisture presence, with dew
points in the mid-upper 60`s in the Upstate and in the mid-70`s here
in the Midlands. So as temps climb into the upper 90`s, some weak
mesoscale lift will develop along the eastern flank of this trough-
moisture gradient. Instability even across the Midlands will be
somewhat limited due to poor mid-level lapse rates, around 1250-1750
or so J/kg of ML CAPE, but coverage should be fairly widespread
given the bit of enhanced mesoscale forcing.
DCAPE will be pretty high with a deep inverted V, surface temps
near 100 F, and decently widespread convective coverage, so
some isolated strong to damaging wind gusts are possible in
spots this afternoon and evening.

&&

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

- Not as hot on Wednesday and Thursday.

- Shower and thunderstorm chances increase. A few thunderstorms
  may become strong with damaging winds as the primary severe
  hazard.

- High PWATs through the period, combined with weak steering
  flow, suggest a flash flood potential with any convection.

Upper trough centered in the Great Lakes region at the start of
the period slowly shifts eastward and will have an increasing
influence on our weather during the short term. The first impact
will be lower temperatures due to the increased cloud cover
across the FA with near normal daytime temperatures favored on
Wednesday and especially Thursday. The approaching trough could
aid in increasing convective development across the CWA with
CAMs showing development focused in the Upstate on Wednesday
heading eastward in the afternoon and evening. Given the
overall lack of a strong trigger, pulse thunderstorms are
favored and could also form through colliding mesoscale
boundaries and the sea breeze front moving inland. Inverted-V
modeled soundings would suggest that damaging downburst winds
will be the primary severe hazard though this threat will likely
be localized in nature due to the pulse environment. The Day 2
(Wednesday) and Day 3 (Thursday) SPC SWO places the entire CWA
in a Marginal (1/5) risk, which is reasonable given these
parameters. Conditions are similar on Thursday though increased
cloud cover could limit instability. Southwesterly flow ahead of
the upper trough will continue to transport high levels of
atmospheric moisture into the region, with PWATs expected to be
in the 2 to 2.25 inch range on Wednesday and slightly lower on
Thursday. The Day 2 WPC ERO places the entire FA in at least a
Marginal (1/4) risk with a Slight (2/4) near the North Carolina
border. The Day 3 ERO limits the Marginal risk to the northern
half of the CWA. The high moisture and weak steering flow in
addition to long skinny CAPE profiles in modeled soundings favor
a flash flood threat from any thunderstorms that develop.

&&

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

- Near average temperatures Friday, gradually warming this
  weekend as upper ridging likely returns.

- More typical isolated to scattered convection expected during
  the extended, lower during the weekend.

Upper trough lifts out of the CONUS on Friday as ridging likely
returns to the Southeastern US. This should result in a gradual
warming trend during the long term with decreasing rain
chances. Friday may end up similar to Wednesday and Thursday
with near to slightly above normal temperatures and scattered
showers and thunderstorms. Rain chances should be lower and more
isolated this weekend due to the presence of the aforementioned
ridging. Rain chances may increase again early next week as a
cold front attempts to break through the ridge.

&&

.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
VFR conditions through early afternoon, with scattered convection
likely in the mid afternoon-evening along with possible restrictions.

VFR will dominate the forecast period with FEW-SCT cumulus field
developing around 4k-6kft MSL this afternoon. ISOLD-SCT -SHRA/-TSRA
should then develop at all TAF sites, particularly after 08/18z with
the potential for gusty winds to around 25 kts. There may also be
some brief CIG/VSBY restrictions with the stronger TSRA. Otherwise,
sfc winds mainly SLY less than 10 kts with convection diminishing
after 09/00z. Some overnight fog and stratus are possible depending
on rainfall totals and coverage as winds become light and variable.
Very similar conditions expected to develop on Wednesday, though
precipitation coverage may be greater.

EXTENDED AVIATION OUTLOOK...There is the possibility of
diurnally driven showers and thunderstorms this week with the
potential for periodic restrictions.

&&

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

&&

$$