Clemson, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

274
FXUS62 KGSP 250726
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
326 AM EDT Fri Apr 25 2025

.SYNOPSIS...
A stationary front will remain across our area through Saturday
providing a focus for daily scattered to numerous afternoon and
evening showers and thunderstorms. Dry high pressure moves in for
Sunday and Monday. A cold front drops into or near the area through
Thursday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 315 AM EDT Friday: Presence of a diffuse quasi-stationary
boundary within a south to southwesterly flow regime has kept
a very moist airmass in place and has aided in a weak upglide
to keep nocturnal showers ongoing, especially in northeast
Georgia and Upstate South Carolina. The Blue ridge Escarpment
also continues to help redevelop showers across the North Carolina
mountains/foothills. Model guidance lessens in coverage, but doesn`t
totally get rid of the showers by daybreak. Low stratus will also
continue to spread across the region as well, which will lead to
overnight lows running 10-15 degrees above normal.

Still expect a cluster of DPVA to traverse across the CFWA from west
to east Friday afternoon and evening. As a result, the coverage in
diurnal convection is expected to become more widespread compared
to the previous few days. CAMs currently keep an embedded line
of convection following the cluster of DPVA and sends this line
into mountains by the afternoon and east of the mountains by the
evening hours. There are also indications of scattered convection
developing ahead of this line. The environment will only induce
modest instability (500-1000 J/kg) and weak shear, which should keep
any severe threat at bay, but an isolated strong to severe storms
can`t be totally ruled out. Weak MBE velocity vectors and high PWAT
values will elevate a local flash flood threat, mainly in areas that
have received multiple rounds of heavy rainfall over the previous
few days. Heavy rainfall is a welcome site to most locations
however as the rainfall will be considered beneficial. With the slow
progression of the area of DPVA today and tonight, longer duration
showers and thunderstorms are expected and should keep coverage
going into the early overnight hours, especially in locations
where the environment is left untapped. Afternoon highs should
rise a category or so warmer compared to Thursday as slightly
drier profiles aloft and somewhat deeper boundary layer mixing
will help scatter out morning low stratus and other layers of
clouds enough to allow more insolation to reach the surface. In
this case, max temperatures for today will be near-normal for
late April. Lingering cloud debris and rainfall within the moist
airmass will keep overnight lows tonight 10-15 degrees above normal.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 240 AM Friday: A cold front crosses the area Saturday. Good
forcing and copious moisture will lead to numerous showers across
the mountains and scattered showers elsewhere as guidance has
trended back wetter. With the wetter forecast, instability is not as
high, but high enough for isolated to possibly scattered storms.
Severe chances and excessive rainfall look minimal. Drier air
quickly moves in Saturday night and remains in place Sunday as high
pressure slides into the area. Highs Saturday will be 5 to 10
degrees above normal. The drier air mass is also cooler with highs
dropping to around normal Sunday. Lows Saturday night around 5
degrees above normal remains nearly steady across the west on Sunday
night and falls a few degrees over the east.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 255 AM Friday: High pressure moves off shore Monday with a
cold front approaching from the northwest on Tuesday. A moist
southerly flow slowly increases each day with isolated diurnal
convection possible across the mountains both days. The cold front
drops south near the area Wednesday then stalls just north of the
area as low pressure develops along the front to our west and moves
into the Ohio Valley. Expect moisture and instability to increase
across the area both days with scattered, mainly diurnal convection.
Temps ramp back up through the period with temps around 10 degrees
above by Wednesday and Thursday.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
At KCLT and elsewhere: Mess of a forecast with a moist airmass in
place, leading to an abundance of low-level cloud cover hovering at
different ceilings levels. BKN/OVC MVFR/IFR cigs are expected at
all sites and the latest trend has all sites going strictly IFR,
possibly LIFR just before daybreak. Showers have scattered about the
area and current radar observations suggest that the best chance
for SHRA over the next few hours will be at KAVL/KHKY/KAND, so
placed a TEMPO to capture this. Variable low stratus cigs and fog
restrictions will give headaches to overall forecasts, especially
with showers developing as well. Winds will be southerly to variable
through the overnight hours. Low-level clouds will remain in place
throughout the day Friday with SCT/BKN coverage. Expect cigs to lift
to MVFR after daybreak and through the mid ti late morning hours and
are expected to return to low-end VFR by the afternoon and evening,
outside of passing showers and thunderstorms. Best chance for
showers and thunderstorms are expected to by after 18Z Friday and
placed a PROB30 to time the most likely time for thunder at each
TAF site. Winds should veer slightly to a south to southwesterly
component during the daytime period, but not forecasting gusts
outside of nearby thunderstorms. Model guidance hint at another
round of low stratus and vsby restrictions overnight tonight.

Outlook: Mainly diurnal showers/thunder and associated restrictions
will continue Saturday. Fog and/or low stratus may develop overnight
into sunrise each morning, especially where heavier downpours
occurred the previous afternoon/evening. Dry high pressure expected
Sunday and Monday.

&&

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

&&

$$

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