232
FXUS62 KGSP 302346
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
746 PM EDT Thu Jul 30 2026

.WHAT HAS CHANGED...
No significant changes for this forecast cycle.

Updated the Aviation Discussion for the 00z TAFs.

&&

.KEY MESSAGES...
1. Near-normal temperatures with unseasonably low humidity and
no diurnal convection expected through Friday.
2. Another frontal system is expected to arrive from the west
this weekend, possibly stalling across our area early next week,
bringing back high rain chances, below-normal temperatures,
and some potential for locally heavy rainfall.

&&

.DISCUSSION...
Key message 1: Near-normal temperatures with unseasonably low humidity
and no diurnal convection expected through Friday.

Deep, relatively weak ridging will continue to influence the weather
over the East through Friday. This will result in relatively low
humidity, resulting in larger-than-normal diurnal temperature
ranges: max temps near normal and tonight`s low temps around 5
degrees below climo. Afternoon surface dewpoints mostly in the 50s/
minimal instability will result in a very low...if not 0 chance of
diurnal convection.


Key message 2: Another frontal system is expected to arrive from the
west this weekend, possibly stalling across our area early next
week, bringing back high rain chances, below-normal temperatures,
and some potential for locally heavy rainfall.

Deep layer ridging will shift off the East Coast Fri night/early
Sat, as large scale height falls overspread the TN and OH Valleys,
with an upper low possibly closing off to our west by the end of
the weekend. Resultant deep SW flow will advect a plume of deep
moisture...characterized by precipitable water waters of over
2"...into our area ahead of an attendant frontal zone by the
end of Saturday. In the interim, increasing low level moisture
is forecast to allow for sufficient destabilization to support
scattered diurnal convection, mainly across the western half of
the area Saturday afternoon. Instability may be just enough to
support the threat of an isolated pulse severe storm or two.

With the increasing moisture and relative low level jet developing
ahead of height falls, some degree of convective activity is likely
to continue well into Saturday night/early Sunday, with some threat
of locally heavy/perhaps excessive rainfall lingering through the
night in light of favorable environmental factors. The frontal
boundary will likely enter the forecast area by Sunday afternoon,
with continued high moisture levels and some instability (albeit
tempered by widespread cloud cover) supporting the potential
for widespread convective development and a continued locally
heavy/isolated excessive rainfall threat Sunday afternoon/evening.

Beyond Sunday, global models diverge on the fate of upper troughing
and the frontal zone/moisture plume over the East, although there
is a weak consensus that the best ingredients for convection/heavy
rainfall will shift to our east by Monday afternoon. Even in that
scenario, scattered diurnal convection would be expected to develop
Monday. While the global models agree that the deeper moisture
will be to our east by Tuesday, there is also a broad consensus
that a weak upper low will remain closed just west of the CWA into
mid-week, possibly supporting climo+ PoPs for diurnal convection
(i.e., scattered coverage across the mountains; isolated-to-widely
scattered elsewhere) Tue through Thu.

Under widespread clouds and solid convective coverage, max temps are
forecast to be a solid 5 degrees below normal each day from Sunday
through Tuesday, with a gradual warming trend expected to begin
Wed. Min temps will be right around climo during this time frame.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
At KCLT and elsewhere: VFR conditions expected at all our TAF
sites thru the period. There may be some mtn valley fog again in
the Little TN Valley, but little elsewhere. Few to sct Cu expected
thru the period under periods of mainly thin Ci. Wind will be light,
mainly out of the N/NE overnight, then toggling to S/SW by early
Friday aftn. The dry air mass in place should preclude any showers
or thunderstorms for one more day.

Outlook: Shower and thunderstorm chances and associated restrictions
return Saturday and continue into early next week. Low stratus
and/or fog will be possible each night starting Friday night,
mainly in the mtn valleys. More widespread low clouds and fog
expected Saturday night thru Sunday morning.

&&

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

&&

$$

ARK/JDL