447
FXUS62 KGSP 082323
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
723 PM EDT Sat Aug 8 2026

.WHAT HAS CHANGED...
Updated the aviation discussion for the 00Z TAFs.

&&

.KEY MESSAGES...
1. Scattered showers and thunderstorms are expected across the area
each day through Monday, with highest coverage in the mountains. A
few storms could pose a threat of isolated flash flooding and
perhaps one or two severe storms producing damaging wind gusts.
2. Temperatures will climb back above normal on Monday, after
which it will be hot and humid each day through the end of the
week. Some Piedmont/Upstate locations could have afternoon heat
index between 98-103 beginning Monday.

&&

.DISCUSSION...
Key message 1: Scattered showers and thunderstorms are expected
across the area each day through Monday, with highest coverage in
the mountains. A few storms could pose a threat of isolated flash
flooding and perhaps one or two severe storms producing damaging
wind gusts.

Not much change to the pattern over the next couple of days,
with upper ridging reasserting itself from the east, while broad
troughing sets up across the Great Lakes to the Northeast US. Temps
will warm to a category or two above normal, with continued
muggy dewpts in the upper 60s to lower 70s east of the mountains
within a Bermuda High setup. This should result in moderately high
instability each aftn thru Monday. Shear will remain in the 15-20
kt range, which will be marginal for updrafts to organize around
some outflows. Steering flow has picked up a tad, and should veer
more out of the west/northwest starting Sunday, allowing for more
mountain-initiated convection to track out into the Piedmont. Still
expect the bulk of coverage to remain in the mountains. A few
pulse severe storms producing damaging wind gusts. As for heavy
rain threat, PWATs remain high, and storms could merge or train
over some areas. So, isolated excessive rainfall will remain on
the table in this environment.


Key message 2: Temperatures will climb back above normal on Monday,
after which it will be hot and humid each day through the end of
the week. Some Piedmont/Upstate locations could have afternoon
heat index between 98-103 beginning Monday.

Models are in good agreement on the upper pattern shifting to a
broad ridge over the Southern Plains and persistent broad trough
over the eastern CONUS for most of next week. This will set up
a slightly drier west-northwesterly flow regime across the CWFA
from Tuesday thru at least Thursday. The latest NBM has come
in noticeably drier for these periods, especially east of the
mountains, thanks in part to downslope flow. This also results in
slightly warmer max temps. I think the NBM dewpts might be too
high during the aftn hours each day, as dewpts should mix out
at least to the upper 60s to lower 70s, rather than mid 70s. So
while heat index values will likely push into the 98 to 103 range
across much of the Piedmont, confidence on needing a Heat Advisory
remains low. PoPs are mainly confined to the mountains near the
TN border, where convection upstream may try to organize into an
MCS and track toward the Southern Appalachians. Confidence remains
low on that, but forecast trends will be monitored closely. The
12z GFS and Canadian deterministic models continue to show a front
sagging south into the area by Friday, as the eastern upper trough
deepens. However, the 00z ECMWF and the LREF suggest upper ridging
will actually build back in from the west and keep the front to
our north. The latest NBM has PoPs increasing into the 30-50%
chance range east of the mountains. We`ll which trend holds.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
At KCLT and elsewhere: TSRA should diminish through 02z. Heavy
rainfall at KAVL/KHKY increases confidence for IFR BR and low
stratus to return overnight, so TEMPO for KAVL for 1SM vsby. Light
to calm winds overnight and pick up out of the SW Sunday. Another
round of scattered TSRA so PROB30 at some terminals for Sunday,
mainly in the mountains. BKN/SCT cigs should remain VFR outside of
any TSRA.

Outlook: Scattered showers and thunderstorms, with associated flight
restrictions through early next week. Patchy fog and low stratus is
possible each morning, especially in the mtn valleys and anywhere
that received significant rainfall.

&&

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

&&

$$

ARK/CP