280
FXUS62 KGSP 081011
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
611 AM EDT Wed Oct 8 2025

.SYNOPSIS...
A cold front brings isolated to scattered showers and thunderstorms
today with above normal temperatures returning. Dry conditions
develop behind the front Thursday into early next week as high
pressure builds over the region. Much cooler and below normal
temperatures return Thursday into Friday before a warming trend
develops this weekend into early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 608 AM EDT Wednesday: Subtle height falls moving into the CWFA
as an upper trough to the north over Atlantic Canada and the Great
Lakes region propagates eastward with an attendant cold front.
Initial band of showers in association with the encroaching cold
front from the northwest has moved across the mountains, with with
the activity making its way outside of the mountains now. The cold
front is currently draped from the Northeast through the OH/TN
Valleys and into the Lower MS Valley. The front should enter the
CWFA across the NC/TN border by daybreak as current observations
shows it just on the TN side of the border. The front will continue
to push through the CWFA throughout the daytime period and complete
a full fropa later this evening. Scattered showers will be possible
over the area ahead and even right on the backside of the front
through the morning and afternoon hours. CAMs are not excited about
the potential of much convection as cloud cover and the timing of
the front`s arrival will preclude any deep destabilization. However,
as the front moves south and east of the I-85 during peak heating,
the HREF develops ~500-1000 J/kg of SBCAPE ahead of the
boundary and in this case, can`t totally rule out a rogue
thunderstorm or two in these locations with some form of
redevelopment. The better deep layer shear and forcing for
ascent remains north of the region as well, which basically puts
our strong to severe storm risk near zero. Good compressional
heating ahead of the front and only subtle height falls will
allow for afternoon highs to climb a category or so above normal
outside of the mountains and near-normal in the mountains where
the onset of cooler air behind the front starts earlier in the
afternoon.

Otherwise, the front will sag south of the CWFA tonight as a stout
surface high (~1035mb) centered over the Great Lakes region will
nose in strong northeasterly low-level CAA, creating a wedge-like
synoptic setup. The change in a cooler and drier airmass will send
low-end gusty winds overnight, with gusts up to 20-30 mph as the
pressure gradient tighten between the high and front. Clouds will
scattered out and lead to clearer skies, but the boundary layer
won`t fully decouple thanks to the incoming CAA, so overnight lows
remain at or a few ticks above normal.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 100 AM EDT Wednesday...

Key Messages:

1) Cool and Dry with Below Normal High Temperatures Returning

2) Breezy Winds Expected, Especially East of the Mountains

3) Frost Possible Thursday Night into Early Friday Morning Across
Portions of the North Carolina Mountains

Upper troughing will remain over the Southeast through the short
term. At the sfc, dry and cool high pressure will continue to build
into the Southeast from the north through Thursday night. The center
of the sfc high will push off the New England coast Friday but the
SW periphery of the sfc high will remain extended over the region
through Friday night, keeping cool and dry conditions around. Breezy
winds will develop through the period, especially east of the
mountains, with gusts ranging from 15-25 mph. Temps each afternoon
will only reach into the mid 60s to lower 70s east of the mountains
and the mid 50s to lower 70s across the mountains. Thus, highs will
end up ~3-6 degrees below normal each day. Thursday night appears to
not only be the coolest night of the week but the coolest night of
the fall we have seen so far with lows ending up ~3-5 degrees below
normal for most locations. Lows Thursday night will fall into the
mid 30s to lower 40s across the NC mountains, which may allow frost
to develop in the northern NC mountains and in some locations west
of the French Broad Valley. Lows elsewhere will dip into the lower
40s to lower 50s Thursday night. Lows Friday night will be a few
degrees warmer, ending up near normal to just above normal. Frost
may develop again across portions of the NC mountains Friday night,
but it should remain patchy and isolated thanks to slightly warmer
temps.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 130 AM EDT Wednesday...

Key Messages:

1) Dry Weather Sticks Around

2) Breezy Winds Linger East of the Mountains, Mainly Over the Weekend

3) Warming Trend Begins Saturday and Continues into Early Next Week

Global model guidance appears to be coming into better agreement
regarding the both the upper pattern and low-level pattern through
most of the long term, but there remains some disagreement towards
the end of the period. Upper troughing remains over the Southeast
through Saturday before an upper low cuts off from the main flow on
Sunday near eastern NC. Meanwhile, another stronger upper low sinks
southeastward out of the Great Lakes into the Ohio Valley over the
weekend. Sunday evening into Monday morning the stronger upper low
will gradually absorb the weaker upper low off the Mid-Atlantic
coast. Model guidance is then diverges on which path the upper low
will take past Monday morning. The GFS has the upper low lifting NE
while remaining offshore the East Coast on Tuesday while the ECMWF
and Canadian have the upper low stalling off the Carolina coast on
Tuesday. At the sfc, a coastal low will develop off the Carolinas
this weekend but once again guidance is not in agreement regarding
the track of the coastal low towards the end of the period. Like the
upper low, the GFS has the coastal low lifting NE on Tuesday while
the ECMWF and Canadian have the coastal low stalling near the
Carolinas on Tuesday. Regardless of the coastal low stalling or
lifting NE, it appears that the bulk of the moisture associated with
the low will remain east of the GSP CWA thanks to another area of
dry high pressure building across much of the eastern CONUS. Thus,
the NBM maintains dry conditions through the long term which matches
global guidance well at this time. Breezy winds linger east of the
mountains this weekend, with gusts ranging from from 15-20 mph.
Breezy winds may stick around east of the mountains early next week
but confidence is low at this time. Temps will gradually warm
through the period, with above normal temps returning for most of
the long term.

&&

.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
At KCLT and elsewhere: Variable conditions as some terminals
continue to deteriorate into daybreak. A cold front is encroaching
the region from the northwest as the initial band of showers ahead
of the front move across the area. Better coverage of showers are
moving across the Upstate sites and KCLT, which is reflect in the
TEMPO. Not as much confidence for steady -SHRA, so placed a
prevailing VCSH mention instead with a TEMPO for -SHRA and
associated restrictions. The TEMPO was placed for the best timing
for showers and restrictions based on current radar trends and
latest model guidance. Guidance have hit locations along and south
of I-85 hard with IFR cigs/vsbys before daybreak, so placed this at
the Upstate sites in the TEMPO. Otherwise, the showers will shift
out of the area later today, but kept a VCSH mention into the
afternoon hours as guidance show isolated showers redeveloping along
the front as it moves across the area throughout the daytime period,
mainly outside of the mountains. Winds ahead of the front will
general run south-southwesterly and quickly shift northwesterly once
the front slides through the terminals. Timed this up in the TAF,
but the expectation is for this to occur early- to mid-afternoon,
with the exception of KAVL, where the wind shift occurs during the
morning hours. Winds continue to shift later in the day into tonight
behind the front, going from northerly and eventually northeasterly
by the end of the period. Elevated gusts filter in once the
component toggles to a north-northeasterly component, so placed a
gust mention at all the TAF sites for later this afternoon through
the evening, and even lingering into the overnight hours.

Outlook: Drier conditions return Thursday and persist for the
remainder of the week and into the weekend. Patchy morning fog/low
stratus will be possible in the mountain valleys each day, otherwise
VFR conditions expected.

&&

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

&&

$$

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