685
FXUS62 KGSP 211757
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
157 PM EDT Fri Aug 21 2026

.WHAT HAS CHANGED...
Flash flood potential is increasing for isolated locations east of
the I-77 corridor.

Temperatures are trending slightly cooler for next week.

&&

.KEY MESSAGES...
1. Another round of showers and thunderstorms for the area through
this evening. A few storms may be severe, producing damaging wind
gusts, locally heavy rainfall and isolated flash flooding.
2. Drier weather returns Sunday through early next week, with
afternoon shower and thunderstorm chances returning by midweek.

&&

.DISCUSSION...
Key message 1: Another round of showers and thunderstorms for the area
through this evening. A few storms may be severe, producing damaging
wind gusts, locally heavy rainfall and isolated flash flooding.

An upper trough swings a weak cold front through the TN/Ohio Valley
and makes a run for the Carolinas tonight. Ahead of it, showers and
thunderstorms make a return for another round of convective fun that
may linger into the overnight hours. Destabilization is helping to
fuel showers and thunderstorms already ongoing in the Upstate. A
Severe Thunderstorm Watch has been issued for a portion of the
Upstate, mainly along and south/east of I-85 and a portion of the NC
Piedmont through 9 PM. the main area of concern for the severe
threat still remains along and east of I-77, which includes the
Charlotte Metro, and counties in SC to the south of I-85. For this
the Storm Prediction Center has issued a Slight risk (threat level 2
of 5), mainly for damaging winds. Given the higher moisture amounts
ahead of the front, a small risk for locally heavy rainfall and
flash flooding is possible, especially for urban areas and locations
that received rainfall this morning. Model guidance seems to hint at
the greater potential for heavy rainfall and flash flooding is east
of I-77, especially just east of Charlotte. Current guidance depicts
2-3 inch/hour rain rates so cannot rule out the potential for flash
flooding. It depends on where these storms setup and how much
destabilization can occur over the next few hours. Model guidance is
not in consensus with timing or coverage, but given the location of
the front and anticipated arrival, expect the potential severe
threat to ramp up from now through 9 PM. Could have a few lingering
storms as the front moves in, but looking at shower chances quickly
dropping off throughout the night. Regardless of the exact locations
and timing, always remember to have multiple ways to get a warning.
If you are outdoors and hear thunder or see lightning, seek shelter
and never drive through flooded roadways.


Key message 2: Drier weather returns Sunday through early next week,
with afternoon shower and thunderstorm chances returning by midweek.

Behind the front, drier and somewhat cooler air moves into the area
by Sunday, shunting rain chances for a a few days. As a surface high
migrates eastward over the Midwest and into the northeast portion of
the country, reduced moisture and air from the north contribute to a
welcomed break in heat as temperatures look to dip into the 80s for
most of the area through the end the forecast period. As the high
moves offshore by midweek, moisture slowly starts to return and
increases rain chances once again. Mostly expecting the typical
summertime afternoon shower and thunderstorm activity to resume.
Overall, calmer and slightly cooler weather ahead.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: SHRA and TSRA for all terminals with the
higher confidence being at KCLT. A TEMPO for KCLT 21z-01z for TSRA
and a PROB30 01z-04z for any lingering TSRA. PROB30 for all other
sites for TSRA through 00z. Patchy BR/FG possible at all sites
overnight, with highest confidence at KAVL, hence a TEMPO for 1/2SM
FG from 09z-13z. After a front moves through, expect quick
improvement Saturday morning into the afternoon. Winds remain
VRB/light outside of any TSRA, with a light NW direction Saturday.

Outlook: Quieter weather returns after Saturday. Mountain valley fog
and low stratus is possible each morning.

&&

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

&&

$$

CP