470
FXUS62 KCAE 060037
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
837 PM EDT Tue Aug 5 2025

.SYNOPSIS...
Showers remain possible this evening and overnight. The
atypical cold air damming pattern lingers through the workweek
before a coastal low erodes the wedge this weekend. Below normal
high temperatures can be expected each afternoon through at
least Saturday despite a gradual warming trend Wednesday into
the weekend. Shower and thunderstorm chances stick around this
week, with the potential for locally heavy rainfall each day.

&&

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

- Isolated to scattered showers possible again tonight.

- Any additional moderate to heavy rainfall will increase the
  likelihood of localized flooding, especially on the saturated
  grounds across the northern CSRA into the northern tier of SC
  counties in the FA.

The region remains close to the right entrance region of an
upper jet and solidly wedged in for the most part with the
surface front near the southern part of the FA. Lingering upper
divergence and enhanced moisture convergence near the front
brought convection across the southern tier of counties in the
area this evening, which has largely pushed out and to the
south. There does remain a batch of light rain pushing across
the Midlands at this time, but this is not expected to have much
of an impact in terms of additional rainfall. Some of the area
rivers/streams where the axis of heaviest rain fell this morning
are continuing to rise and a couple are expected to reach their
crest into Wednesday morning. When this is combined with CREST
soil moisture percentages that are between 50-75% across the
northern CSRA and our northern SC counties, any additional
moderate to heavy rainfall likely will exacerbate any ongoing
flooding, or possibly lead to new areas of flooding. There is a
bit of a mix in models overnight tonight and into Wednesday
morning where recent HRRR, RAP, and 3km NAM runs continue to
suggest more scattered showers, possibly with some convective
activity, mainly along and north of the I-20 corridor while the
HRW suite and experimental RRFS are not as impressed in coverage
or intensity.

With some approaching vorticity aloft and PWAT`s
over 2", current thinking is additional scattered shower
development will occur in GA before pushing into the region
during the overnight and into early Wednesday. The bigger
uncertainty is if this activity can tap into already weak
elevated instability. This is something that will continue to be
monitored overnight and into Wednesday morning, especially with
the now sensitive nature to the northern FA to convectively
driven rainfall or even moderate stratiform rain.

&&

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

- Little change in the thinking for the middle of the week, with
numerous showers and below average temps.

High pressure remains over the area in a cold air damming
configuration through the period while an upper level trough remains
over the area with a series of short waves moving through the flow.
The forcing combined with a moist east to northeast flow keeps
showers over the area through the period. Looks like the best chance
for thunderstorms and locally heavy rainfall is Wednesday afternoon
when elevated instability and PWATs are higher. Thursday looks to
have good coverage of showers but lighter QPF. Highs will be below
normal Wednesday with clouds and showers in place. Thursday looks to
be a couple of degrees warmer with lighter precip. Lows near normal
Thursday night creeping back toward normal Thursday night.

&&

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

- Continued shower activity expected through the long term
  period. Monitor for the likely development of a coastal low
  this weekend.

The damming high pressure will slowly weaken through the period
even as it remains in place. The weak upper trough remains in
place as well with continued weak short wave activity moving
through the flow. A low pressure center develops near the SC
coast Friday or Saturday and moves slowly north along or near
the coast through the period. Forecast models differ on the
strength and location of the low but agree that a moist easterly
low level flow remains over the area. The guidance blend
moderates the features keeping generally scattered mainly
diurnal convection in place through the period with only a low
chance of heavy rainfall. This looks to be a good compromise for
now given the uncertainty. Highs slowly increase back to near
normal by Monday and Tuesday. Lows increase to above normal.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Ceiling and visibility restrictions will continue overnight and
through much of Wednesday.

Surface front remains stalled out south of the forecast area,
and will remain so through Wednesday. North of this front, wedge
pattern continues, with expected mvfr/ifr conditions at all taf
locations for much of the next 24 hours. Currently, sites are a
mixture of mvfr/ifr ceilings, but guidance is consistent with
bringing those ceilings below 1kft and into ifr/lifr between
03z-06z, and keeping those restrictions in place through
Wednesday. See no reason to differ from guidance at this point,
so much of the same from past few days will remain on tap. Light
showers or even a storm will be possible through the period, and
will handle with vcsh and tempo groups as timing becomes more in
focus. Winds light and either variable or slightly out of the
east.

EXTENDED AVIATION OUTLOOK...Flight restrictions are possible
each day with widespread showers expected into the weekend.

&&

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

&&

$$