124
FXUS62 KGSP 081154
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
654 AM EST Sat Nov 8 2025

.SYNOPSIS...
Showers and isolated thunder continue through tonight, waning
toward morning.  On-and-off rain chances continue through Sunday.
A strong cold front crosses the area by late Sunday, ushering in a
cold Arctic air mass, and resulting in accumulating snowfall across
parts of the North Carolina mountains, continuing into Monday.
Thereafter, dry and chilly conditions persist into next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 650 AM Saturday: Rain has ended across the area, with enough
clearing skies to allow areas of fog to develop. There are some
patches of dense fog, including the I-40 corridor east of the
Escarpment in which a Special Weather Statement is in effect until
8 am. The fog should start to lift after sunrise, but cannot rule
out a brief period of some widespread dense fog.

Otherwise, A leading shortwave trough will cross the Central
Appalachians and exit off the Mid-Atlantic coast this morning,
leaving the forecast area with a quasi-zonal flow ahead of another
shortwave that is diving into the mean longwave trough over the
Plains. This will effectively back the mid-level flow atop the
forecast area and stall out a weak cold front somewhere invof
the southern part of the CWFA.  Currently, a band of convection
associated with the front oriented nearly east-west is crossing
the forecast area as expected. The northern part of the line is
weakening to just some showers as it enters the I-77 corridor,
while a few storms continue across the southern NC mountains. The
latest RAP has MLCAPE of around 500 J/kg working into NE GA and the
Upstate from the SW, which may allow for a tstm or two to continue
as the convection pushes off the Escarpment. With that said, the
severe threat should continue to wane, as storms become roughly
parallel to the steering flow and lose the better bulk shear. The
00z CAMs are in good agreement that this activity will largely
taper off and exit to the SE by 12z this morning. Patchy fog may
form behind the rain, but widespread dense fog is not expected.

Later this morning, residual stratus should mix out by midday,
resulting in partly cloudy skies for the aftn. The front that
triggered this morning`s convection will stall out across the
forecast area, and may be a trigger for another round of convection
late aftn thru this evening. The 00z guidance has all come in
pretty agreement on scattered showers and possibly a few storms
developing across the southern half of the forecast area by 00z
and expanding/tracking NE across the NC foothills and Piedmont
thru the evening hours. The initial activity will have up to 1000
J/kg of sbCAPE to work with, but track into less unstable air. Bulk
shear of 50-60 kt may be enough for a few strong storms. The CAMs
show a discrete storm mode with a few updraft helicity swaths,
but they are weak. Highs will 5-10 deg above normal, mainly mid
70s east of the mountains.

Tonight, convection should work NE of the area late evening, as
a warm front lifts thru the area. Areas of low stratus and patchy
fog will be possible across mainly the NC foothills and Piedmont
before daybreak Sunday. Lows will remain well above normal.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 1217 AM EDT Saturday...

Key Messages:

1) Isolated showers may develop across the I-77 corridor,
especially south of I-85, on Sunday afternoon and evening, ahead
of a cold front.

2) Accumulating snowfall is expected across the higher elevations
of the NC-TN border on Sunday night, and flurries may continue
through Monday.

3) A hard freeze is expected Monday night, with temperatures
falling well below freezing across the entire forecast area.

By Sunday morning, several h50 vort lobes will be embedded in
a broad baroclinic zone extending from the Ozark Plateau into
the upper Ohio Valley and Quebec.  The most notable of these
features will migrate from the Ozarks into the Tennessee Valley
during the day Sunday, amplifying as it does so, and driving a
surface cold front across the western Carolinas in the process.
For most of the day, zones ahead of the front will remain just
capped enough that little to no convection is expected.  However,
there will be a very brief opportunity for some convection to fire
across the southeastern Piedmont, where guidance suggests that
daytime mixing may successfully break the cap.  Deeper residual
subsidence, however, still looks like it`ll limit the depth of the
unstable layer, hindering instability and importantly, limiting
effective shear such that even if convection does develop over
the far southeastern tier of our counties, it`s unlikely any of
it will be severe.  Based on the latest CAM output, the better
chances for any convection - even showers - are farther east.

So, the bigger story is what comes behind the front.  By late
morning if not sooner, the front will have cleared the mountains
and strong CAA will have developed.  Surface temperatures will drop
steadily through the day while a tight 4-6mb pressure gradient
develops across the Appalachians.  Despite this, even the higher
end of guidance only depicts Advisory-criteria wind gusts at the
higher elevations...though given breezy winds and chilly temps,
it`s possible wind chills could warrant a cold-weather product
as we get closer to the event.  In any case, winds aside, it`s
more certain that 850mb temps will be cold enough to support some
ice nucleation in the mountains by sunset.  So, would expect NW
flow precipitation to begin as rain showers in the morning...but
flurries are possible at the higher elevations as early as sunset,
and by midnight, the entirety of the NC mountains will be under
the gun for snow.  Accumulations look tame in and north of the
French Broad Valley.  Across the Smokies and Balsams, however,
there`s the complicating issue of a possible shallow unstable layer
in the low levels, which will develop just as a second, trailing
shortwave axis arrives from the Tennessee Valley.  This could
significantly raise snowfall rates in the southern NC mountains,
albeit only for a short period of time...and so accumulations of
2-3 inches...with isolated, high-elevation spots in the Smokies
seeing >3 inches...appear possible across these zones.

Come morning, there`s the additional issue, raised in previous
forecasts, of whether any of this snowfall could manage to escape
into the NC Foothills.  It still looks like the likely answer is:
no.  Several things would need to line up for this scenario to work
out...first, enough lingering moisture would need to remain in place
through dawn Monday that any precipitation is still falling in the
Foothills, and second, the 850mb low would need to sag far enough
south that temperatures in the Foothills fall to freezing before
that moisture vanishes.  Right now, fewer than 25% of long-range
ensembles depict the Foothills getting cold enough to support snow
flurries; fewer still get the cold air there in time to catch any
lingering moisture.  So the chances are low...but never zero.

Finally, dry weather will push in for Monday.  NW flow snow may
continue across the Tennessee border for much of the day and
into the first part of Monday night, but everywhere else, skies
should clear, giving way to a dry and chilly Monday, with highs
not making it out of the 30s in the mountains and only climbing
into the mid 40s across the low terrain.  Monday night, a steady
5-10kt WNW wind will continue.  Despite the lack of radiative
cooling, temperatures should fall well below normal amid persistent
CAA...into the mid-20s across the low terrain, and well into the
teens in the mountains...for our first hard freeze, and by far
the coldest night of the season so far.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 1232 AM EDT Friday...

Key Messages:

1) Chilly conditions continue throughout the extended period.

2) Dry conditions linger through next weekend.

The upper pattern will continue to deampify on Tuesday, with
flat, WNW upper flow persisting through at least Wednesday on the
periphery of residual longwave troughing over eastern Canada.
Surface high pressure centered over the Gulf Coast will gently
migrate eastward, slowly modifying and allowing lows to rebound
slowly Tuesday and Wednesday night.  Another shortwave appears
likely to cross the Mid-Atlantic on Wednesday, but low-level
convergence and theta-e fields indicate that no frontal passage will
occur; rather, the new air mass should settle into the Deep South
and Tennessee Valley...eventually expanding into the Carolinas late
Thursday or Friday, but with no clearly-defined frontal boundary.
Either way, profiles look to remain so dry through the period
that no rain, nor even any extensive cloud cover, is likely.
Get ready for a cold week!

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: Areas of fog and low stratus have developed
across the area in the wake of earlier rainfall. The fog and
stratus should start to lift and scatter out after sunrise, with
all sites going VFR by around noon. Whatever low clouds do develop
should scatter out to VFR by noon, leaving a cu field around
4000-5000 ft. Late aftn thru this evening, scattered showers and
possibly a few tstms are expected to develop, mainly across the
Piedmont. Will continue with PROB30 for SHRA at all our sites,
except KAVL. Thunder chances still look too low to mention in the
TAFs, but may be needed if confidence increases. Precip will lift
north overnight, and leave very moist low-levels to support fog
and stratus development again before daybreak Sunday. Guidance is
in good agreement on LIFR cigs in the NC Piedmont with possibly
dense fog at KHKY. Wind will generally favor a SW direction thru
the period, except NW at KAVL this morning.

Outlook: A strong cold front will cross the area from the west on
Sunday, bringing gusty winds with low clouds and RA/SN showers
in the mountains.  Precipitation may linger Monday across the
mountains. Gusty winds linger through Monday into Tuesday. Dry
conditions Wednesday and Thursday with afternoon gusts possible.

&&

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

&&

$$

SYNOPSIS...MPR
NEAR TERM...ARK
SHORT TERM...MPR
LONG TERM...MPR
AVIATION...ARK