Area Forecast Discussion
Issued by NWS Columbia, SC

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603
FXUS62 KCAE 300702
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
302 AM EDT Mon Jun 30 2025

.SYNOPSIS...
Typical summertime weather is expected to continue into the
start of the work week, with near to slightly above normal
temperatures and daily shower and thunderstorm chances. More
widespread showers and storms Tuesday and Wednesday and slightly
cooler. Summer pattern returns for the second half of the week.

&&

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

- Upper trough becomes diffuse with near normal temperatures
- Scattered afternoon/evening showers and storms

The upper trough that has been over the region for several days
becomes diffuse while the upper ridge over the western Atlantic
ridges into the area. Again, little change in the atmospheric
conditions with PWATs remaining high around 1.7-1.9 inches with
MLCAPE values around 1000-1500 J/kg with weak wind shear. Hi-res
guidance favors convection along the sea breeze where best
surface convergence will exist and expect scattered diurnal
convection, similar to previous days. Severe threat remains low
and feel the localized flooding threat is there also given slow
storm movements in unorganized pulse convection. Temperatures
will be near normal with highs in the lower 90s while overnight
lows fall into the lower to mid 70s with some lingering debris
clouds.

&&

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

- Widespread showers and storms associated with an upper trough.
  Rain will likely be heavy at times with marginal risk of flash
  flooding.

Tuesday, an upper trough will approach the area from the
northwest with flow shifting out of the southwest, advecting
significant deep layer moisture into the area from the Gulf.
PWATs expected to increase over the course of the day with the
HREF indicating a 50 to 60% probability of values greater than 2
inches. The strongest forcing will likely remain west of the
area through much of the day with diurnally driven showers and
storms developing in the anomalously moist airmass. As the
trough shifts into the area Tuesday evening, showers and storms
likely become more widespread with efficient rain rates as the
NAEFS mean shows PWATs exceeding the 90th percentile across the
area. Unlike previous days, forcing will allow convection to
continue well after sunset and into the overnight period.
Northwestern half of the forecast area remains in a marginal
risk of excessive rainfall from WPC mainly due to the
anomalously high PWATs and long, skinny CAPE profiles. Storms
should be moving fast enough to limit any significant flooding
problems, however. Overall severe risk remains low with moderate
destabilization and limited organization as strongest deep
layer shear remains well north of the area. With increased
moisture and a breakdown of the ridge, expect highs a few
degrees cooler, in the upper 80s to low 90s.

The upper trough will continue to shift through the area during the
day Wednesday which will continue to allow for waves of showers and
storms that will diminish from west to east over the course of the
day. WPC ERO extends the marginal risk for Wednesday through the
rest of the forecast area with a similar synoptic setup and
efficient rain rates expected to continue along with moderate
destabilization, especially in the eastern portion of the
forecast area. Cooler once again Wednesday with highs generally
in the mid to upper 80s. Lows for both Tuesday and Wednesday in
the low 70s.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Key Message(s):

- Near normal temperatures with isolated afternoon convection
  each day.

More typical summer pattern returns through the extended period with
heights recovering as temperatures return to normal with highs in
the low to mid 90s and lows in the low to mid 70s. Northwest flow
develops with ensemble means indicating upper ridging builds over
the central US. This will lead to some drier air moving in aloft
with PWATs also returning to near normal. As the axis of the upper
ridge shifts into the area for the weekend, broad subsidence
expected to return to the area which will overall suppress
convection. Still chance for isolated storms, mainly favoring the
sea breeze but blended guidance generally favors limited coverage of
any convection that develops each day in the long term.

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
Generally VFR conditions expected through the forecast period
outside of convection.

Similar pattern continues over the area with weak upper ridging
as the upper trough to our west becomes diffuse. Another round
of afternoon and evening scattered convection which could result
in temporary restrictions. Winds generally light from the south
less than 5 mph through sunrise then picking up to 6 to 8 mph
by afternoon. Convection should wane during the evening hours
with some lingering debris clouds. Possible vsby restrictions in
predawn fog but confidence is low.

EXTENDED AVIATION OUTLOOK...Patchy ground fog possible each
night...but is unlikely to cause significant issues at the
terminals. A front will approach the Southeast Tue/Wed leading
to increased thunderstorm chances.


&&

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

&&

$$