424
FXUS62 KGSP 302316
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
616 PM EST Sun Nov 30 2025

.SYNOPSIS...
Drier conditions briefly return to the area on Monday ahead of the
next low-pressure system, which will bring widespread precipitation
to the area Monday night into Tuesday. Behind the system, high
pressure will result in chilly and dry conditions Wednesday and
Thursday.  Unseasonably cold and unsettled weather is expected
Friday as another system brings more precipitation to the area.

&&

.NEAR TERM /THROUGH MONDAY/...
Key Messages:

1) Precipitation and cool temps continue ahead of a cold front.

2) The next system approaches late Monday afternoon cold air
damming sets up.

As of 604 PM EST Sunday: The last band of precip is quickly
diminishing as the cold front crosses the TN/NC border and continues
to moves eastward. Temperatures remain well above freezing across
the CWA, so any falling precip should remain liquid.

With the front to our east, a quick transition to high pressure
will take place overnight, but with only varying degrees of
clearing. Winds are already picking up a bit int he mountains with
the front, so not expecting much in terms of fog development.
However, should the winds decrease and clouds clear out, there could
be some fog or low end stratus by daybreak, but would remain patchy
at best. Expect a gradient of low temps from N to S, with locations
north of I-40 dropping below freezing but locations across the lower
Piedmont staying closer to normal (upper 30s).

By daybreak Monday, the sfc high will have already bridged the mtns
and the familiar cold air damming wedge-like configuration will
be in the process of developing across the western Carolinas. The
sfc high will be weakening on Monday as the center moves from the
Midwest to the Hudson River Valley through the day, but moisture
return will be underway by afternoon from the southwest ahead of the
wave lifting out of the upper trof well to the west. Warm advection
and isentropic upglide will develop and spread northeastward
late in the day, helping to establish the wedge. The increasing
clouds and northeast flow will keep temps below normal and in
the 40s. The main forecast problem looks like the timing of
precip onset. The fcst was based on the blend, but the trend in
the guidance is toward holding off until after sunset with light
precip reaching the ground. This seems very reasonable. In fact,
the 12Z CAMs support this scenario. Expect the precip probs for
Monday to drop accordingly in the next package.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
As of 100 PM EST Sunday:

Overall, there is not much change in the pattern that drove previous
forecast package, and as such, confidence continues to increase that
accumulating freezing rain for the northern mountains and eastern
Blue Ridge Escarpment will result in at least some brief travel
impacts for the area Monday night into Tuesday morning.  Dry high
pressure will set the stage Monday with dewpoints in the 20s as
cyclogenesis occurs over the western Gulf.  Expect increasing clouds
from this system Monday afternoon as moisture advects overhead,
with some rain showers likely across the western zones beginning
around sunset.  The timing of the increasing cloud cover across
the northern zones may allow for some radiational cooling at onset,
before saturation of the column can occur and precip begins closer
to midnight Tuesday.  Since the northern mountains and highest
elevations of the central and northern Escarpment will struggle
to reach the upper 30s Monday afternoon, this combination of brief
radiational cooling and wet-bulbing will allow areas to drop below
freezing before or around precip onset.  Therefore, a period of
freezing rain is likely, primarily between 11pm to 6am Tuesday
morning, along the Escarpment from central McDowell County to
Caldwell County and across much of eastern Mitchell and all of Avery
counties.  As always, the forecast struggles with the challenges
of latent-heat release from rainfall freezing on surfaces, cold-air
advection (which there is very little of due to the transient nature
of the source high pressure), and precipitation rate (more intense
rainfall can actually limit ice accretion).  While we are pretty
confident in the occurrence of freezing rain in the aforementioned
locations, details regarding amounts and the timing of transition
to all rain will need to be fine tuned overnight tonight.  As such,
in close collaboration with our neighbors, we will wait to issue
any hazard products until Monday morning, if necessary.  No matter
what, precipitation will transition to all rain across the impacted
zones before mid-morning Tuesday.

Forecast sounding profiles suggest that the higher elevations of
the central and southern mountains will generally be too warm for
frozen precip.  It cannot be ruled out that a very brief period of
sleet or freezing rain may occur closer to onset, but given that
many of these higher elevations will be firmly embedded within the
warm nose itself and initial surface cooling will be inhibited by
cloud cover, any meaningful impacts appear unlikely.

Elsewhere, including across most of the mountains and all of
the foothills and Piedmont, temperatures will remain well-above
freezing with highs east of the mountains in the lower 50s.
Liquid precipitation amounts are expected to be quite healthy as the
system traverses the region Tuesday, with widespread accumulations
of 0.75" to 1.25" likely and isolated higher amounts possible
before the system departs early Tuesday evening.  These amounts
will be beneficial to the region and pose no flooding threat.

The timing of the system departure may impact higher elevations,
especially along the TN border, which will drop below freezing
fairly quickly later Tuesday afternoon into the early evening hours
as moisture departs the region.  Right now, the expectation is
that moisture will depart before temps become critical; however,
any slowing of this timing may necessitate a chance of light
snow in these locations in next forecast package.  Fortunately,
dry conditions return on Wednesday behind this system with only
slightly cooler high temperatures, as return flow to our west
inhibits any meaningful cold-air advection.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 100 PM EST Sunday:

The extended begins on Thursday with what is likely our warmest day
east of the mountains, as dry high pressure, higher thicknesses,
and weak downslope flow support high temperatures near normal.
The next shortwave trough digs into the southern Plains Thursday
night as high pressure quickly traverses the Ohio Valley and
Mid-Atlantic.  Once again, cyclogenesis occurs near the western
Gulf Coast as moisture rapidly advects toward the region overnight
Thursday into Friday morning.  Compared to the system earlier
in the week, the strong, 1033mb high pressure may briefly anchor
itself over the Mid-Atlantic states during this time, a backdoor
cold front would initiate CAA across the region overnight, and
CAD would develop as precip begins to fall across the region
early Friday morning.  Temperatures at this time appear cold
enough that the initial precipitation may fall in a frozen form
across a significant portion of the area, but modest diurnal
heating will transition much of this precipitation to all rain,
especially across the mountain valleys and east of the mountains.
Once again, the highest mountain elevations and favored areas
of the northern mountain region may not recover significantly and
frozen p-types may dominate through Saturday morning.  Nevertheless,
right now, Friday looks to be a cold and wet day across the area,
with temperatures potentially 15-17 degrees below normal area wide.
At this time, there is decent agreement among the deterministic
guidance on the timing of this next system, but ensemble guidance
shows greater spread, with many members showing onset later on
Friday.  Obviously, this forecast has plenty of time to evolve,
but the evolution of this system will need to be closely monitored.

Given the cold high temperatures, it will take comparatively less
effort to cool to critical temperatures Friday night.  Guidance is
suggesting that a secondary shortwave may ride along the southern
stream and bring a second round of precipitation to the forecast
area, with the precipitation gradient increasing from northwest
to southeast.  At this time, temperatures may approach freezing,
especially across the western NC mountains and the central
and northern mountains.  With a strong inversion in place, if
temperatures drop below freezing, the primary threat may be a brief
period of freezing rain Friday night into Saturday morning before
temperatures warm, with highs on Saturday reaching the lower to
mid-50s east of the mountains.

There is enough spread among the ensemble guidance that the NBM
maintains precipitation chances into Sunday.  However, confidence
is extremely low on timing and potential winter weather impacts
and as such, the resultant weather grids are low confidence as well.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: IFR/LIFR continues across most of the
terminals ahead of a cold front slowly pushing through the area.
Conditions should improve overnight as -RA and cloud cover
decreases. Winds should become light at most terminals overnight,
with the shift becoming N/NE. However, expecting the winds to be VRB
with the weakening front outside of the mountains. KAVL could see
low-end gusts through 11z. There is a possibility for some mountain
valley BR at KAVL/KHKY IF skies clear quick enough and winds calm,
but confidence is low. Expect all sites to return to VFR Tuesday and
through the end of the TAF period. Another system moves in just
outside the TAF period, so a PROB30 at all sites except KHKY. Winds
on Tuesday should remain NE except at KAVL where winds toggle more
S/SE.

Outlook: Widespread MVFR to IFR conditions return Monday night with
light FZRA possible early Tuesday morning in the mountains. VFR
conditions return Wednesday. Another system may affect the region
Friday into the weekend.

&&

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

&&

$$

SYNOPSIS...JMP
NEAR TERM...CP/PM
SHORT TERM...JMP
LONG TERM...JMP
AVIATION...CP