Rock Hill, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

965
FXUS62 KGSP 130552
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
152 AM EDT Wed Aug 13 2025

.SYNOPSIS...
Abundant moisture over the Southeast will keep scattered to numerous
showers with mainly afternoon thunderstorms through Thursday. As a
somewhat shallow upper ridge builds over our region during the
weekend and early next week, temperatures warm to near normal.
Afternoon thunderstorms become more isolated to scattered into early
next.

&&

.NEAR TERM /THROUGH TONIGHT/...
Key Messages:

1) Muggy conditions stick around through the near term.

2) Widespread rainfall expected overnight and into Wednesday, with
isolated flash flooding concerns possible.

As of 125 AM EDT Wednesday: Starting off the forecast period in a
soupy mess of showers and gross humidity. Ongoing showers and
thunderstorms are currently moving across the CWA from the SW and
should continue throughout the night, especially across the mountain
zones. Taking a look at the synoptic setup, A weakening trough over
the central CONUS pushes eastward and gets absorbed into the general
flow today. Meanwhile, high pressure over the Atlantic churns and
brings a conveyer belt of moisture into the area, along with
embedded shortwaves through the day and into Wednesday evening. The
first shortwave is enhancing rain fall currently sweeping across the
CWA. Guidance from CAMs overnight show multiple rounds concentrated
across the mountains and NC Foothills. The PMM from the SHREF
continues to back off on rain total amounts, however, in this broad
warm sector with PWATs well over 2 inches, there could still be
areas with locally higher amounts. Looking at 1-2" through Wednesday
night, but higher amounts can occur with any convective cells. With
500-1000 J/kg of sbCAPE still lingering across the mountains, higher
rain amounts are possible. After daybreak, again, multiple rounds of
rain in the mountains as the next shortwave curves around the
western edge of the high pressure system. For this, the Weather
Prediction Center keeps portions of the area in a Slight Risk (level
2 of 5) for excessive rain. One factor working in favor of not
contributing to even higher rainfall amounts are the light SW
surface winds. This significantly reduces the amount of mechanical
lifting along the terrain and keeps from piling up the rain totals.
Regardless, in this soupy environment and already saturated ground,
any rain that does fall is likely going to cause flooding issues
especially in poor drainage areas, lower points, and roadways. By
Wednesday night, PoPs go down to 30-50% as the high pressure axis
shifts. Temperatures don`t change and remain in the mid to upper 80s
east of the mountains.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 120 AM Wednesday: Heights slowly rise across the Southeast as
a trough moves east of the area and an anticyclone builds from the
Gulf Coast into the Mid-south. At the surface, high pressure settles
over the southern Appalachians with a lee trough remaining in place
to its east. A cold front approaches from the NW on Thursday but
dissipates before reaching the area. It then redevelops to our south
on Friday. The very moist and moderately unstable air mass remains
in place Thursday with numerous showers and scattered thunderstorms
during the afternoon and evening. The deep moisture moves out of the
area for Friday, returning the sensible weather to more of a typical
summertime diurnal convective pattern. Highs rise to near normal
Thursday then slightly above normal for Friday. Despite the drying,
dew points will be high enough Friday for a smattering of heat index
values around 100 along and south of the I-85 corridor.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 145 AM Wednesday: The upper anticyclone centered over the Mid-
south slowly retrogrades allowing a northwesterly flow to develop
over our area by Tuesday. Surface high pressure remains over the
area through the period. A cold front moves toward the area from the
NW Monday and Tuesday but never reaches our area. The relatively
moist and moderately unstable air mass over the area Saturday leads
to scattered diurnal convection. The diurnal convection becomes more
isolated, with potential for scattered coverage over the mountains,
through the rest of the period with an overall slightly drier air
mass. Highs steadily rise to a few degrees above normal by Monday
then drop back a few degrees below normal for Tuesday. The drying
air mass helps keep the heat index below 100 degrees through the
period.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
At KCLT and elsewhere: Showers and TSRA continue overnight with a
mix of VFR/MVFR across the sites to start. Will keep mostly VCSH and
SHRA for the overnight hours at most terminals as these storms lose
steam. Once the rain clears out, vsby/cig restrictions return with
IFR in the early morning hours. At this time, KCLT looks to remain
just at the VFR level and confidence isn`t there to prevail MVFR
before sunrise. But there could be a quick dip into the MVFR
category just before sunrise. At KAVL, a TEMPO for 1SM vsby from
09z-12z and 2SM at KHKY for the same time. Improvements return in
the later morning hours as 5-10 kts winds pick up out of the SW.
Another day ahead with multiple rounds of showers and TSRA possible
so covered this with yet another PROB30. Towards the end of the TAF
period, vsby restrictions return, especially for the mountains
terminals.

Outlook: Showers and thunderstorms with associated restrictions
are expected across the area each day this week. Morning fog/low
stratus is also possible, especially across the mountain valleys.

&&

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

&&

$$

SYNOPSIS...RWH
NEAR TERM...CP
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...CP