248
FXUS62 KGSP 171746
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
146 PM EDT Fri Oct 17 2025

.SYNOPSIS...
Dry conditions persist before a stronger cold front arrives Sunday,
bringing a chance for a few showers and thunderstorms. Dry and cool
conditions return next week, and linger through the end of the
period.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of midday Fri: Upper ridge axis now centered from Michigan
to the Floida Panhandle will shift eastward thru the near term,
aligning with the Mid-Atlantic coast by Saturday evening. 850mb
ridge and surface high thus also move eastward, promoting more
solidly SW flow and likely aiding in some low level moisture
return. Subsidence inversion will keep deep convection at bay and
PoPs will remain near zero thru Saturday.

The same subsidence inversion should limit the depth of diurnal
mixing, but nonetheless dewpoints did tumble in our NE CWA early
today where the dry sfc high had most influence. With RH having
dipped into the 30s percent, did go a bit below NBM for dewpoints
this afternoon, although a slow upward trend should occur. As SW
flow becomes steadier, expecting min temps to trend warmer compared
to Fri morning--generally 4-7 above normal. By the same token,
less potential for mixing and localized RH minima on Saturday,
even as max temps trend warmer, ending up around 10 above normal.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
Key Messages:

1) A cold front brings a chance for showers and thunderstorms Sunday
afternoon and into the evening.

2) Severe weather chances are low for Sunday.

3) Near freezing temperatures possible behind the front on Sunday
night at elevations above 5000ft.

4) Dry conditions return Monday.

As of 125 PM EDT Friday: By Saturday night, the ridge that had been
plaguing the eastern CONUS is pushed offshore as a strong, digging
trough ejects out of the central U.S. During the overnight hours,
guidance agrees with a strong low developing quickly as the trough
pushes and lifts E/NE into Sunday, bringing a relatively strong cold
front through the Ohio/TN Valley and eventually the CWA. At this
time, the frontal boundary looks to pass through the region starting
during peak heating on Sunday afternoon through the overnight hours.
Showers and thunderstorms are possible, but there are a lot of
limiting factors. First, the shear profiles are more than enough to
support severe weather, 60-70 kts in the mid-levels. But, this could
be for nothing as the better forcing remains outside the CWA as the
trough turns more neutrally tilted by Sunday afternoon. Another
factor reducing confidence in a severe threat at this time is the
lack of instability. Modeled soundings from various guidance show
the area struggling to gain even a few hundred J/kg of sbCAPE. This
would be even more reduced should the timing of the front come
through earlier in the day before decent heating can take place. So,
all this to say, the severe threat confidence is low but non-zero.
Cannot rule out a strong thunderstorm with locally heavy rainfall
and a rumble of thunder. As the front pushes into the area and the
trough swings by to the north, winds are expected to increase,
especially at the higher elevations. Current guidance depicts a
tight pressure gradient with this strong trough, however, guidance
keeps the area well below Wind Advisory criteria for Sunday.
Additionally, the QPF response is nothing impressive with a range of
0-0.25 inch, with higher amounts, still under an inch, in the
mountains. Behind the front, much cooler and drier air filters in
and returns the area to a quiet pattern for the remainder of the
short term and into the next. Temperatures dip to just below normal
on Monday and overnight temps make a run for just above freezing at
the higher elevations (above 5000ft). Given the breezy winds Sunday
night, frost shouldn`t be an issue at this time.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
Key Messages:

1) Weak and dry cold front passes midweek.

2) Temperatures dip well below normal behind the front, with near
freezing temps possible at the higher elevations.

As of 130 PM EDT Friday: The extended portion of the forecast is
much quieter than the weekend. Synoptically, the southeast remains
in relatively zonal flow as a new upper low forms over the Midwest
on Tuesday. This disturbance deepens and swings over the Great Lakes
by midweek, bringing a very weak and dry frontal passage through the
area. It`s so destitute that the front may not even be noticed. What
should be felt are the much cooler temps and perhaps the winds
across the mountains. As the low churns to the north, guidance has a
tight pressure gradient over the northern portion of the CWA,
increasing winds at the higher elevations. Being so far out, this
will change depending on where the low sets up to the north. As for
temperatures, behind the weaker front by midweek, guidance does have
overnight temps reaching freezing in a few areas across the
mountains. Will continue to monitor. Regardless, none of these
parameters show anything of real significance weather wise across
the area through the end of Day 7.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: A bit tricky to pin down sfc winds this
afternoon with competing influences of sfc high to our east and
light SW`ly flow mixing in at the top of the PBL. Result looks to
be mainly SSW to SW winds although periods of VRB possible at all
sites. Some low VFR cumulus will be seen near and south of KAND,
but otherwise just FEW cirrus thru late this afternoon. Cirrus
increase in coverage tonight, likely being BKN at times, but
still look to scatter by morning. VFR flight conditions most
likely at all sites, but there remains possibility of mountain
and river valley fog near daybreak, with SW winds promoting some
moisture return and good radiational cooling potential if/where
cirrus remain transient. KAVL just gets 6SM and SCT003 for now but
trends will need to be monitored. More solidly SW winds Saturday,
also breezier/gustier, with VFR cumulus likely over the mountains
(KAVL) after 18z.


Outlook: A cold front may bring showers and associated restrictions
Sunday along with breezy conditions. Dry conditions return on
Monday. A dry cold front may bring breezy conditions again on
Tuesday.

&&

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

&&

$$

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