Rock Hill, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

790
FXUS62 KGSP 060617
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
117 AM EST Sat Dec 6 2025

.SYNOPSIS...
Cool high pressure will move past the region today and Sunday,
but then an upper level disturbance will bring another round of
precipitation for late Sunday night and Monday. The middle part of
next week will be dry with temperatures returning to normal. The
next cold front should arrive late in the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1:05 AM EST Saturday: An area of sct precip continues to
make its way eastward over CAE`s area to our south. A broad deck
of low stratus will persist over our region thru the overnight
and much of the morning as a stalled, moist frontal bndy lingers
just to our south. With light to calm winds across our area and
RH values near saturation, we are already seeing some patchy fog
develop over the SC Upstate and NC Piedmont. If the fog becomes
more prevalent over the next few hrs, we will likely need an SPS
or possibly a Dense Fog Advisory for portions of our fcst area.
Low temps this morning will be near to slightly above normal for
most of our fcst area.

Otherwise, another wave of weak low pressure will move east along
the above-mentioned frontal boundary to our south. This will bring
a return of deeper moisture, weak isentropic lift, and low-end light
rain chances, mainly along and south of the I-85 corridor late this
morning and into the early afternoon. The low moves east of our area
during the afternoon taking the lift with it. The low clouds are ex-
pected to lift thru the afternoon and will likely sct out, first over
our higher terrain and then south and east. This should help erode
the wedge and allow high temps to rebound a decent amount compared
to yesterday. Nonetheless, highs will still be roughly 5 to 10 deg
below normal for early December.

&&

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

1) Some light snow possible late Sunday night and Monday over
the mountains, but right now areas east of the mountains are most
likely to only get cold rain.

2) Temps remain below normal.

As of 1235 AM EST Saturday: The main feature of interest continues
to be a southern stream short wave forecast to make a run at the
western Carolinas Sunday night and then crossing the region on
Monday, while cold air makes an attempt to drop south across the
region. Needless to say, the timing of this interplay is difficult
and uncertain roughly 48 hrs out. Confidence in the track and
timing of the wave is decent enough, arriving in the early morning
Monday and then moving across the region in the first half of
the day. The wave should have enough moisture with it to wring
out some light precip. However, most of the forcing will be at
mid-levels. Not really seeing much in the way of upper divergence
or low level isentropic lift or frontogenesis across our region,
so that figures to be a limiting factor. Thermal profiles suggest
this will be either a rain or snow situation, which simplifies
things. Confidence is better for an elevation-dependent rain/snow
combo across the mtns starting in the pre-dawn hours, because
there will be enough cold air aloft over the higher terrain so the
p-type is less dependent on the arrival of the colder air from the
north. Outside the mtns is much less certain. As it looks right
now, most of the precip would be moving off to the east before
it would cool off sufficiently across the foothills and western
Piedmont for much in the way of snow. Plume diagrams don`t look
great, either. Bottom line...right now little stock is placed in
the operational GFS in its depiction of significant snow amounts
over the mtns and extent of snow east of the mtns. Signs point
toward an Advisory-level event mainly over the nrn mountains for
Monday morning.

Otherwise, temps will remain below normal. Sunday looks close to
normal for highs, but Monday should be on the order of ten degrees
under normal with the early precip and clouds. The cold air surge
will eventually arrive, so overnight lows Monday night will be
well below freezing.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Key Messages

1) Quiet through mid-week with a warming trend back to normal
temperatures.

2) Breezy Wednesday ahead of an approaching cold front.

3) A potential cold front passage late Thursday or Friday could
bring cooler temps and another chance of precipitation.

As of 1254 AM EST Saturday: Guidance shows the region remaining
under a broad long-wave upper trof through the middle part of
the week with the main sfc high, though relatively weak, moving
across the region on Tuesday. This would keep temps about ten
below normal for Tuesday highs, but the sfc high moves off to
the east Tuesday night. If all goes according to plan, the high
to our east and the passage of a fairly strong clipper low over
the Great Lakes Wednesday would quickly increase the southwesterly
warm advection flow with a low level jet translating east overhead
during the day. That results in a quick rebound to near-normal
temps Wednesday afternoon. Assuming mixing is deep enough, there
would be the potential for breezy southwest winds through the day
and into the overnight hours. Signs still point toward another
strong nrn stream short wave dropping down into the trof late in
the week, digging and sharpening the trof and pushing a strong
cold front toward our region on Thursday. Passage would be either
Thursday night or Friday morning, with precip being mostly rain
with some high elevation snow potential. There would be a decent
chance of some NW flow snow on the TN border behind the front in
this scenario, with temps falling back down into the realm of ten
degrees under normal for the weekend.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: Numerous restrictions will continue overnight
and into the morning as widespread low stratus and areas of fog per-
sist over the area. IFR to LIFR cigs are expected at most terminals
with periods of dense fog also fairly likely. The latest guidance
suggests that fog development is less likely at KAVL despite the
light to calm winds, however it remains possible thru the morning.
Eventually, conditions will improve heading into the afternoon and
there may end up being a fairly sharp gradient between the low stratus
and VFR, which could bring rapid improvement once the retreating bndy
lifts back north. This should bring a return to VFR at all terminals
by the late afternoon to early evening. Winds will remain light and
VRB to calm thru the morning, and eventually pick up from the SW
during the afternoon. They are expected to go light to calm again
later this evening. At KAVL, calm winds will eventually take on a
NWLY direction this afternoon, but will likely be light and VRB
at times thru the day.

Outlook: Another round of low stratus and fog is possible Saturday
night into Sunday morning across portions of the foothills and Pied-
mont. Another storm system may bring more precip and associated
restrictions Sunday into Monday. Drying high pressure is expected
to spread back over the area by early Tuesday.

&&

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

&&

$$

SYNOPSIS...PM
NEAR TERM...JPT
SHORT TERM...PM
LONG TERM...PM
AVIATION...JPT