Area Forecast Discussion
Issued by NWS Columbia, SC

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676
FXUS62 KCAE 101807
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
207 PM EDT Thu Jul 10 2025

.SYNOPSIS...
The threat for damaging winds and localized flash flooding will
continue across the forecast area this afternoon/evening due to
the passage of an upper trough to our north. This trough is
replaced by ridging this weekend, allowing temperatures to
slowly rise with typical summertime showers and thunderstorms.
The ridge breaks down early next week, leading to cooler
temperatures and higher rain chances once again during the
middle of next week.

&&

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

- Widespread showers and thunderstorms expected this afternoon and
evening with damaging winds and flash flooding possible.

A slow moving trough will continue to shift eastward today and serve
as a focus for convective development. Upper support will gradually
increase toward evening, with a shortwave pushing along the NC/SC
border. Diurnally driven pulse convection will continue to develop
with strong heating, as earlier cloudiness is now dissipating and
pushing eastward. As such, low level lapse rates are increasing as
temperatures push into the mid and upper 80s, likely settling in the
low 90s for highs this afternoon. The surface environment remains
muggy with dewpoints in the low to mid 70s. Forecast soundings are
saturated through the column, and satellite estimates once again
paint the entire forecast area with PWAT values over 2.0". Overall
shear remains limited so expect the convective mode will still be
pulse, but with storms having a bit more forward motion as southwest
flow aloft is slightly stronger. This certainly won`t rule out
training, and therefore we`re still concerned about a flash flooding
threat. In particular, areas north of the I-20/I-26 interchange will
be closely watched due to heavy rainfall and flooding which occurred
on Wednesday, boosting antecedent soil moisture levels. Regarding
the potential severe aspect, current MLCAPE values are around 1500-
2000 J/kg as any residual CIN continues to erode. DCAPE values are
quite low with little dry air aloft, so the damaging wind threat
will likely be due to precip loading. Hi-res guidance is consistent
in developing a widespread field of convection over the next few
hours. Of particular interest is the HRRR solution, which has been
developing a line of stronger-looking storms moving through the
northern CWA in conjunction with the aforementioned shortwave
generally around 00Z this evening, over the last several runs. So
we`ll need to see if this comes to fruition, as it may boost the
flooding threat further. Overall, another quantity over quality day
is expected with at least a few strong to severe storms given the
widespread coverage.

&&

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

- Scattered afternoon/evening showers and storms expected each
  day.

- Temperatures gradually warm through the weekend.

The upper trough that has brought more widespread
showers/storms will begin its exit Friday as 500mb heights
slowly rise through the day and moisture decreases some with
mean HREF PWAT`s being between 1.8-2.0" as flow turns a bit more
westerly. One last piece of shortwave energy brings another
shot at scattered storms during the afternoon and evening
Friday, though the recent 12z HREF mean solution and its members
depict coverage being less than has been seen the past couple
days, likely due to decreasing moisture and heights that will be
slowly rising. Storms that do develop however, will bring
similar risks to those from the previous days as ample
instability is shown in forecast soundings (MLCAPE of 1500-2000
J/kg). With high moisture lingering above a decently mixed
boundary layer, some gusty downburst winds will be possible in
the strongest storms as they collapse. Due to this potential,
the whole CWA is in a Marginal Risk for severe weather Friday
(level 1 out of 5). Luckily the influence of the upper trough
brings increasing flow aloft and thus while storms in this pulse
environment will still have slower motions, they will at least
have some steering flow to allow them to translate. Long/skinny
CAPE profiles over deep moisture will bring another day with a
potential for heavy rainfall and possible spots of flash
flooding, especially toward the northern Midlands and a swath
from Burke County GA toward Barnwell, Orangeburg, Aiken, and
Lexington Counties, where increased soil moistures will make
these areas a bit more sensitive to heavy rain.

This weekend, upper troughing is replaced with ridging and
moisture that returns to more seasonable levels. The building of
ridging will allow hot/muggy conditions to move back into the
region as heat indices peaking around 100-105 will be possible,
mainly Sunday. More typical summertime convection is expected
each day as PoP`s become more isolated to scattered each day.

&&

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

- Above normal temperatures on Monday with heat indices peaking
  between between 100-105.

- Upper ridging breaks down into the midweek, bringing near
  normal temperatures and increase rain chances.

The EC Ensemble and GEFS mean 500 mb anomaly solution are in
decent agreement with ridging remaining overhead Monday,
bringing another day with heat indices that top out near 105 and
climatological precip chances. This ridging slowly breaks down
during the midweek as an area of low pressure approaches the
Bahamas, aiding in turning low level flow more southeasterly to
easterly and bringing PWAT`s near 120% of normal and increasing
PoP`s. Increased PoP`s look to keep temperatures closer to
normal as well into the mid week.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Periodic restrictions through the TAF period with stratus, followed
by showers and thunderstorms this afternoon into this evening.

This afternoon, expect SCT-NUM SHRA/TSRA at all TAF sites.
Restrictions are expected with the strongest storms due to
likely heavy rainfall, particularly impacting VSBYS. Best chance
for TSRA generally 19-01z with showers or storms in the
vicinity an hour or two before and after this window. Winds with
TSRA may be gusty up to around 30 kts. Outside of convective
gusts, surface winds generally SLY at 10 kts or less.

Debris cloudiness expected overnight with winds dropping to light
and variable to calm. Expect additional CIG/VSBY restrictions toward
daybreak Friday, particularly at locations which receive heavier
rainfall today. Guidance is keying in on CAE/CUB/OGB in
particular.

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.

&&

$$