584
FXUS62 KGSP 061455
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1055 AM EDT Sun Jul 6 2025

.SYNOPSIS...
Tropical cyclone Chantal will move into and across the coastal plain
of the Carolinas today and tonight. Hot and more humid conditions
will return on Monday and linger through midweek featuring daily
afternoon and evening shower and thunderstorm chances. The heat
abates somewhat into the weekend but daily afternoon and evening
shower and thunderstorm chances continue.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1030 AM: Chantal has been downgraded to a TD as of the 15z
advisory, being centered about 80 mi west of Wilmington. Intense
rainfall is occurring near the center of circulation, with 3"
reported between 9-10 AM at Lumberton, NC. CAMs have been pretty
consistent in tracking the area of heaviest rainfall just east
of our CWA, with the last couple of HRRR runs and the HiRes-ARW
matching radar imagery fairly well. Those models, and CAMs in
general, lend confidence to appreciably lower PoPs for most of our
zones than what had been depicted on earlier NBM runs. Revised PoP
trends thru 06z tonight to that effect, keeping a sharp gradient
with 70-90% PoP east of I-77 tapering down to a chance for the
lower Catawba River, with unmentionably low values now across
the middle of the CWA. There is some consistency in developing
isolated showers/storms near the SW Blue Ridge Escarpment and
propagating them south into the Savannah Valley, so a mention
is made there as well. Potential for 1-2" total rainfall does
persist along our eastern border and we retained the "Elevated"
category of Flooding Rain Threat in that area as depicted on
the NWS Hurricane Threats and Impacts display, although impacts
probably will remain nuisance-level.

Our eastern zones are expected to remain on the western periphery
of the storm`s circulation with mainly just rain and 20-30 mph
wind gusts thru mid-afternoon. Low altitude cloud cover over the
I-77 corridor thru most of the day, so high temps should remain in
the lower to mid 80s over those zones as previously expected. In
the western half of our CWA, high temps should be near normal,
and perhaps slightly above normal in the French Broad and Little
TN Valleys owing to downslope NE`ly flow off the ridges.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 115 AM Sunday: Chantal moves away from the area Monday leaving
a warm, moist, and weakly unstable air mass across our area. This
air mass remains across the area on Tuesday. Expect diurnal
convection both days, with coverage favoring the mountains dropping
to isolated coverage south of the I-85 corridor in the Upstate and
NE GA. Highs will be on the rise both days with mid 90s common
outside of the mountains and around 90 in the mountain valleys, and
may increase a couple of degrees on Tuesday. Dew points should mix
out both afternoons with relatively deep mixing and weak westerly
flow. Still, heat index values will rise to around 100 degrees or
slightly higher along and south of the I-85 corridor. If temps or
dew points end up warmer, then a Heat Advisory may be needed.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 145 AM Sunday: A couple of short wave troughs will move east
near or over the area through the period. This brings lower heights
and a "cooling trend" with temperatures falling to "only" slightly
above normal by the weekend. A stationary front to our north will
see a series of low pressure centers move east along it. While they
stay to our north, a lee trough develops each day helping to provide
focus for convective initiation. The air mass remains moist and
unstable, so increasing, mainly diurnal PoP is expected each day.
Wednesday will see the highest heat index values, again around 100
or slightly higher along and south of the I-85 corridor. Mid 90s to
possibly 100 will be common through the end of the rest of the
period.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
At KCLT and elsewhere: Tropical Storm Chantal is currently making
landfall over the NC/SC Coast. It is still expected to turn north
and pass roughly 50 to 150 miles east of KCLT later tonight. The
tightening pressure gradient between Chantal and high pressure
centered along the Blue Ridge will keep winds out of the N to NE
in the 6 to 12 kt range thru this evening with low-end gusts of
15 to 20 kts. KAVL will be closer to the ridge axis which should
keep their winds lighter thru the taf period.

For CLT: Much of the latest near-term guidance has been backing off
on lower cigs reaching KCLT over the next several hrs. Thus, opted
to keep any cig restrictions in a TEMPO group as opposed to
prevailing. The TEMPO runs from 13 to 17z and also includes -SHRA
with MVFR vsby. Still have prevailing -SHRA beginning around
17z this afternoon with a PROB30 for SHRA from 18 to 24z today.
It remains unclear whether the heavier rain bands associated
with Chantal will actually reach KCLT, but it`s looking more
likely that they will end up only seeing sct showers
today/tonight with any IFR conditions remaining to their east.
Precip chances taper off this evening with the rest of the
period expected to be dry. There is still a chance that MVFR
cigs may move back over the site around 00z this evening and
then sct out during the overnight, but it`s looking less likely.
Otherwise VFR thru the period with PROB30s and/or VCSH for
SHRA/TSRA potential. Winds will be similar to KCLT just slightly
weaker, especially at KAVL.

Outlook: More typical summertime weather returns on Monday and
continues thru mid-week, with sct SHRA/TSRA mainly in the aftn/
evening and fog and/or low stratus possible each morning.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.

&&

$$

SYNOPSIS...RWH
NEAR TERM...Wimberley
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JPT/Wimberley