Wind Advisory 20, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
638 AM EST Sun Dec 28 2025

.SYNOPSIS...
Cloudy and cooler today with spotty rain or drizzle. A cold front
brings showers late tonight into Monday and ushers in still colder
air Tuesday. Near-normal temperatures return mid to late week. A low
pressure system could bring precipitation to the area for the
weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 632 AM EST Sunday:

Key Message #1: "Backdoor" cold front moves across the area,
bringing markedly cooler temperatures and light rain/drizzle chances
today.

An upper ridge axis is progged to slip across the CWFA tonight in
response to a digging longwave trough moving across the west-central
CONUS. Surface high over Quebec and the northeastern CONUS will
nose into the CWFA, setting up an in-situ CAD. Behind the ridge
axis, low-level winds above the surface will turn southerly,
leading to better moisture advection atop the wedge, which in turn
promotes isentropic lift. By daybreak, most of the CWFA outside
of the mountains will be socked in by a deck of low stratus as the
easterly component from the developing wedge helps to blossom this
stratus layer via upslope from the Blue Ridge Escarpment. CAMs are
developing pockets of drizzle across this portion of the CWFA
between daybreak and the afternoon hours, when the moist upglide is
most prominent. Only promoting slight chance PoPs as the QPF
response is light and measurable precip will be spotty with the lack
of much forcing outside on isentropic upglide. With the in-situ CAD
locked in for the majority of the daytime period, expect afternoon
highs to drop off rather significantly compared to Saturday with
values dropping 15-20 degrees, while still being slightly above
normal for late December.

Key Message #2: Strong cold front encroaches the area from the
west with much colder air behind it to go along with gusty winds.

Surface high will slip offshore and in a position where surface
winds turn south-southwesterly ahead of a strong cold front by
tonight. A closed upper low is shown moving into the Northern Plains
and Upper Great Lakes region overnight tonight as the attendant
frontal boundary encroaches the region from the northwest and should
be in the vicinity of the NC/TN border by daybreak Monday. Model
guidance show a rather quick CAD erosion as WAA takes over. However,
still think some form of residual cold pool will be in place and
keep temperatures relatively the same from the daytime period,
especially in locations closer the Blue Ridge Escarpment where the
stratus layer will remain strong. Model guidance show very deep
surface cyclogenesis with the parent low during the forecast period,
which will create a very tight pressure gradient. Expect winds to
increase, especially over the higher elevations by the end of the
forecast period. Current forecast has borderline Advisory criteria
by 12Z Monday, mainly above 4000' so a Wind Advisory can't be ruled
out but decided to punt this decision to the next forecast cycle
due to lower confidence. Temperatures will be in the process of
dropping over the mountains near the immediate TN border as the
CAA behind the front rushes in. However, a good chunk of this will
hold off until the short term forecast period.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 1225 AM EST Sunday...

Key Message #1: Gusty winds continue across the area Monday behind a
departing cold front and persist across the mountains into Tuesday.
Cold wind chills Monday night over the NC mountains.

Windy to very windy conditions develop across the area on Monday
behind a departing cold front. The wind tapers off outside of the
mountains during the evening but lingers across the mountains into
Tuesday, albeit at lower speeds. Wind gusts will likely be above
Wind Advisory criteria above 5000 ft and possibly above 3500 ft.
Right now, the coverage of locations above 3500 ft appears to remain
small enough to preclude an advisory at this time; however, one may
still be needed if coverage increases. A cold air mass moves in
behind the front as well, with morning highs across the mountains
and late morning or early afternoon highs elsewhere. The cold air
mass, lows around 10 degrees below normal across the mountains and 5
to 10 below normal elsewhere, will combine with the winds to produce
single digit above and below zero wind chills across the mountains.
For now, it appears any values colder than 5 below will be limited
to the highest elevations of the NC mountains. That said, only
slightly colder values could put the northern mountains into play
for a Cold Weather Advisory.

Key Message #2: Good rain chances remain across the mountains Monday
but looking more scant elsewhere. A very brief changeover the NW
flow snow possible for the NC mountains Monday afternoon.

The speed of the cold front and more westerly low level flow will
limit precip chances outside of the mountains. There will be a
decent coverage of showers across the mountains but only a brief
period of isolated to low end scattered coverage elsewhere. Any QPF
on Monday will be very light. A brief period of NW flow snow may
develop Monday afternoon before the moisture dries up; however, even
the most favored high elevation locations will likely get little
more than a dusting.

Key Message #3: Cold and dry conditions continue Tuesday.

Highs Tuesday will be around 15 degrees below normal across the
mountains and 5 to 10 below normal elsewhere. The air mass is also
very dry, so RH values will drop below 25% across most of the area
outside of the mountains. Despite the lighter winds, Increased Fire
Danger could result. Lows Tuesday night 10 to 15 degrees below
normal across the mountains and 5 to 10 below normal elsewhere, but
with lighter winds, will preclude the need for a Cold Weather Adv.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 1255 AM EST Sunday...

Key Message #1: Dry with temperatures gradually warming through
Friday.

Dry sfc high pressure builds over our area from the west Wednesday.
A clipper type system moves by to our north Thursday with dry high
pressure for Friday. Temperatures start our near or slightly below
normal Wednesday rising to near to a little above normal by Friday.
Critical RH values continue Wednesday in the very dry air mass with
some small recovery possible Thursday and Friday, but those days
could also see low RH.

Key Message #2: A southern stream low pressure system could bring
precipitation to the area Saturday.

A southern stream low pressure system moves near or across the area
Saturday. The GFS is weaker an more suppressed with this system
while the ECMWF is stronger and farther north. The Canadian shows a
phasing system with a stronger cold front moving into the area. The
ECMWF has enough cold air for a wintry mix over the northern
mountains/foothills. The GFS is all rain, mainly due to the more
southern track. The Canadian is all rain with more warm air moving
north ahead of the stronger cold front. The GEFS is wetter than its
Ops model, but not as wet as the other two, leading credence to a
potentially wetter scenario. For now, have followed the model blend
which has chance PoP but no significant wintry precip.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
At KCLT and elsewhere: Conditions have quickly deteriorated as
expected as a low stratus deck has blossomed across all of the
terminals. Winds will generally run east-northeasterly through the
morning hours. The low stratus deck will initially produce MVFR
cigs, but a lot of the sites outside of the mountains have dipped to
IFR and even LIFR. Expect this to remain in place throughout the
daytime period with pockets of drizzle and light showers developing
as well. Winds will toggle to a south to southwesterly component
shortly after sunset, while the low stratus deck begins to lift back
to IFR/MVFR cigs and potentially scatter out, however, confidence is
low on the potential for full scattering. Fog is more likely to
develop tonight as better moisture moves into the area, ahead of a
strong cold front. Placed a PROB30/TEMPO at all terminals for timing
of RA/DZ and the best timing for lowest restrictions. Wind gusts
will pick up during the early morning hours Monday from west to east
as the strong cold front moves into the mountains. The front will
shift across the area between 12Z-21Z Monday as winds toggle to a
northwesterly component behind the front with gusts increasing to 20-
30 kts at all TAF sites, mainly after 12Z Monday.

Outlook: Lingering restrictions expected into Monday with CAD
and/or with arrival of stronger cold front from the west. Higher
rain chances Monday ahead of the cold front. Dry and VFR conditions
return behind the front by late Monday, lingering through the rest
of the workweek.

&&

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

&&

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

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
315 AM EST Sun Dec 28 2025

NCZ033-048>053-058-059-062>065-501-503-505-290815-
Avery-Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-Graham-
Northern Jackson-Macon-Southern Jackson-Transylvania-Henderson-
Caldwell Mountains-Burke Mountains-McDowell Mountains-
315 AM EST Sun Dec 28 2025

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...Today and tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

A robust cold front will move through the area on Monday bringing
gusty winds in its wake. Wind gusts of 35 to 50 mph with locally
higher gusts will be possible Monday afternoon through Tuesday
morning, especially in higher elevations above 3500 feet. Wind
chills may fall into the single digits above and below zero in some
of those areas as well.

.SPOTTER INFORMATION STATEMENT...

None.

GAZ010-017-018-026-028-029-NCZ035>037-056-057-068>072-082-502-504-
506>510-SCZ008>014-019-101>109-290815-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Alexander-Iredell-
Davie-Catawba-Rowan-Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-
Union-Greater Caldwell-Greater Burke-Eastern McDowell-
Rutherford Mountains-Greater Rutherford-Polk Mountains-Eastern Polk-
Cherokee-York-Anderson-Abbeville-Laurens-Chester-Greenwood-
Oconee Mountains-Pickens Mountains-Greenville Mountains-
Greater Oconee-Greater Pickens-Central Greenville-
Southern Greenville-Northern Spartanburg-Southern Spartanburg-
315 AM EST Sun Dec 28 2025

This Hazardous Weather Outlook is for northeast Georgia, Piedmont
North Carolina, western North Carolina and Upstate South Carolina.

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.