295
FXUS62 KGSP 112354
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
754 PM EDT Fri Sep 11 2026

.WHAT HAS CHANGED...
Increased the PoPs this evening to reflect latest radar trends
across the southern parts of the forecast area.

Updated the aviation discussion for the 00Z TAF issuance.

&&

.KEY MESSAGES...
1. Hot and humid conditions continue today through much of the
weekend with at least scattered showers and storms, especially
tomorrow.
2. A backdoor cold front pushes through the area on Monday bringing
drier but still warm weather through much of next week, excluding
daily mountain showers/storms.

&&

.DISCUSSION...
Key message 1: Hot and humid conditions continue today through
much of the weekend with at least scattered showers and storms,
especially tomorrow.

Scattered to numerous showers and thunderstorms have been oozing
northward into our NE GA and southern Upstate counties so far this
evening. Outflows from this activity are advecting higher dewpts
and more unstable air, but with the sun setting and much drier air
to the north, convection is expected to struggle developing along
the outflows as they reach the I-85 corridor. There will be some
lingering convection thru late evening, but should wane by around
midnight. A couple more strong to severe storms will be possible,
and isolated excessive rainfall cannot be ruled out.

A weak split flow regime remains draped across the CONUS today with
strong northern stream flow extending from the Northern Rockies
across the Northern Plains and into southeast Canada. Farther
south, a weaker branch of southern stream flow is situated from
the Desert Southwest across the Southern Plains and into the
southeast states.  Within the southern stream, a weak shortwave
trough with a closed upper low is sliding across the Mississippi
Valley and into western Tennessee. This feature will cross the
Southern Appalachians tomorrow with general troughing lingering
into Sunday. An unseasonably warm and humid airmass is entrenched
across the region with afternoon highs today soaring well above
average into the upper 80s to low 90s. Weak height falls ahead of
the approaching trough in concert with a late summer airmass will
help instigate at least isolated to widely scattered showers and
thunderstorms this afternoon, especially south of I-85. A few of
these storms may become strong to marginally severe with the main
hazard being locally damaging winds.

The passage of the upper trough tomorrow will provide more notable
forcing with the 12z suite of CAMs in generally good agreement on
scattered to numerous afternoon/evening showers and thunderstorms
across much of the area. Near-storm forecast soundings reveal tall
skinny CAPE profiles with modest DCAPE. While not overly impressive,
a few isolated strong to severe storms with locally damaging winds
cannot be ruled out again on Saturday. Associated cloud cover will
help to keep temperatures a few degrees cooler compared to today,
but still above climo for mid September. The upper trough axis
gradually pivots across the region on Sunday and another bout of
isolated to widely scattered showers and storms can be expected,
but of lesser coverage compared to Saturday.


Key message 2: A backdoor cold front pushes through the area on Monday
bringing drier but still warm weather through much of next week,
excluding daily mountain showers/storms.

Heading into the start of next week, a notable northern stream
trough is progged to swing across the Great Lakes and into New
England Sunday night into Monday. A sprawling surface high quickly
translates into the Mid-Atlantic and New England and in turn drives a
back door cold front down the Appalachians through Virginia and
across the Carolinas. A few isolated showers and/or a storm may
accompany the front, but it will mainly be a dry frontal passage for
most. Temperatures ahead of the front will once again climb back
into the upper 80s to low 90s. For the remainder of the week, stout
upper ridging builds back over the Southern Appalachians with
guidance indicating 500mb heights nearing 598dam. Gross. Despite
persistent dry northeast flow afternoon highs will rebound through
the week with upper 80s to near 90 common again by Thursday and
Friday, which remains well above climo for mid September. Dry air
will also shunt deeper moisture to over the mountains which is where
the best chances for a few diurnal showers and storms will reside.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: A slow-moving line of showers and
thunderstorms is slowly drifting north across the Upstate and NE GA,
with some convection possibly affecting the Upstate sites over the
next 2-3 hours. Confidence remains on the low side, as convection is
expected to gradually weaken after sunset. Confidence is even lower
at KCLT, but will leave a PROB30 there, as an outflow boundary
has moved in. Overnight, expect mostly VFR mid and high clouds
to linger, but an MVFR to possibly IFR stratus deck is expected
to form around daybreak Saturday across the Piedmont, in addition
to the typical mountain valley fog. These clouds may hold on thru
midday to early aftn, before scattering out to VFR. Guidance still
shows scattered to numerous convection across the area Saturday
aftn. Will continue with PROB30 for TS during peak heating time
frame. Given such high coverage expected, will go with prevailing
SHRA at all sites and TEMPO for TS at KCLT Saturday aftn thru
00z. Winds will be light, mainly out of the S, except VRB around TS.

Outlook: Scattered afternoon and evening storms will once again be
possible Sunday. Storm chances shift to the mountains Monday through
much of next week. Mountain valley fog/stratus will be possible
any given morning, especially in prone/traditional locations.

&&

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

&&

$$

ARK/TW