707
FXUS62 KCAE 061039
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
639 AM EDT Sun Jul 6 2025

.SYNOPSIS...
Tropical Storm Chantal is expected to make landfall early this
morning, tracking mostly across eastern SC/NC through the day and
into Sunday night. Heavy rain possible in the eastern portion of the
area today. As the low moves away from the region we return to hot
temperatures and a return to more diurnal showers and
thunderstorms.

&&

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

- Tropical Storm Chantal expected to bring impacts to the
  northeastern forecast area.

Update: TS Chantal made landfall as of 4a this morning near
Litchfield Beach, SC. The rest of the discussion remains fairly
relevant.

TS Chantal is slowly but surely making its way towards the SC
coastline as of this writing. The center of circulation is
probably 30-40 miles away from making landfall and should come
ashore within the next 3 hours. Strong wind shear aloft has
created an asymmetric system, with the bulk of precpitation in
the eastern semi-circle of the storm. This is forecast to remain
the case over the next 24 hours, making for a challenging
forecast challenge. Right now, the first rainbands associated
with Chantal are rotating into the Pee Dee and eastern
Midlands. rainfall is expected to be light with these as they
push westward. Clouds should slowly increase through the night
as moisture on the western periphery of the storm increases,
though the westward extent of these clouds is uncertain. So much
of the forecast depends on Chantel`s exact track as it pushes
into South Carolina today. PWs are forecast to be in the
2.2"-2.4" range near the center, providing ample moisture for
high rainfall totals. Case in point, HREF LPMM guidance suggest
24h rainfall totals of 2-4" in the Pee Dee. However, HREF
Interquartile Range for rainfall is 0.4"-2.6", casting
significant uncertainty on how much rain actually falls there.
It is simply just dependent on exact track, as the heaviest
rainfall will be along and just east of the center of
circulation. We did consider a Flash Flood Watch in this part of
the forecast area; however, the uncertainty mentioned above
(plus 6hr Flash Flood Guidance around 5") we held off for now.
Elsewhere in the area, the impacts from Chantal are expected to
be minimal. Breezy winds are likely today, with scattered
showers developing this afternoon across the Midlands. The CSRA
will likely remain dry and even sunny for much of the day.
Moisture shouldn`t be as copious as further east & downslope
winds should help to keep things even drier. Highs there should
be in the low 90s, with highs as low as the low 80s in our
eastern counties. Clouds should gradually decrease tonight, with
seasonal lows in the lower 70s.

&&

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

- A return of the heat to start off the week.
- Isolated or scattered afternoon showers/storms possible.

As Chantal moves away from the area, upper ridging will take hold to
start off the week.  With the ridge setting up, a return of the
Summertime heat will be on tap through the short term.  Hot and
somewhat muggy conditions will be common during the afternoon.  With
high temperatures in the upper 90s to around 100, the moisture will
bring heat index readings up to around 105, which remains slightly
below any advisory criteria at this time.  Guidance will continue to
be monitored for higher values and any potential need for heat
advisories early this week.  As for rainfall, a return to more of a
typical afternoon and evening scattered showers and thunderstorms
should be on tap for the majority of the forecast area.

&&

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

- A slight break in the heat from mid-week onward.
- More typical afternoon shower/storm chances expected.

Towards midweek the upper trough may weaken slightly, allowing for
some weak troughing to move in aloft. In addition, at the
surface the region may see the return of lee-side troughing east
of the mountains and into the Piedmont through much of the
longer term. This will bring the potential for slightly higher
rainfall chances each afternoon and evening, especially if any
sea=breeze activity can push far enough into the cwa each
evening. Temperatures will cool off even so slightly with the
upper trough, with afternoon readings in the low to middle 90s
becoming more common by the end of the week.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
VFR conditions in place for now, with MVFR cigs likely to
develop at OGB and eventually CAE/CUB as Chantal moves ashore.

As expected, the TAFs have been a pickle for sure. My hunch that
guidance was too aggressive with ceiling too early seems to have
been correct. Cigs are beginning to slowly but surely develop on
Chantal`s western side, but again are really confined to 60-80
miles west of center. These should move into OGB in short order
but figure to take some time getting into the Columbia sites, if
they make it here at all. The center seems to be moving more
north than northwest, which should keep the bulk of the ceiling
restrictions to our east. So have basically taken out any
mention of predominant MVFR at the Columbia sites and hedged by
including it in my PROB30 for -SHRA at each site. Orangeburg
should still see predominant MVFR with brief IFR in any showers
that develop. The Augusta sites will see predominantly wonderful
weather, with some high clouds and northwesterly surface winds.
All sites should see conditions improve gradually this afternoon
as Chantal moves further away from the forecast area. Calm winds
and mostly clear skies are expected tonight.

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

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...Lake Wind Advisory until 8 AM EDT this morning for SCZ031-037-
     038-137.
GA...None.

&&

$$

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