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062
FXUS62 KGSP 132354
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
654 PM EST Mon Jan 13 2025

.SYNOPSIS...
Cold and dry conditions through much of the week as a series of high
pressure centers move over the area. Temperatures slowly warm to
near normal by late week with precipitation possibly returning by
the weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
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As of 6:15 PM EST Monday: Other than some lingering stratocu
along the NC/TN border and over the northern NC mtns, we remain
mostly clear across our area. Winds will likely remain gusty
over the northern NC mtns tonight and overnight as a tightened
pressure gradient will linger well into Tuesday.

Otherwise, a weak and dry cold front will arrive this evening,
scouring out the last of any lingering clouds and allowing winds
to pick up after midnight as modest CAA settles in and continental
high pressure spills into the Carolinas. Lows will fall back into
the mid-20s Tuesday morning despite winds preventing the boundary
layer from fully decoupling at many locations. So, isolated areas
of black ice will once again be an issue. Elevated NW winds will
persist well into the day as CAA continues, and highs will climb
into the mid-40s.
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&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
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As of 150 PM EST Monday: Amplified winds aloft under mostly
quasi-zonal flow will set the stage for a relatively quiet
short term forecast period. A closed upper low shown drifting
into Atlantic Canada late Tuesday into early Wednesday morning,
while an elongated associated vort lobe sinks southward over
the area and a stout continental polar surface high builds in
across the Northern Great Plains and Midwest will help set the
stage for northwest flow snow showers. In this instance, stout
35-45 kts 850mb northwesterly flow will support orographically
enhanced snow showers in the favorable upslope zones along the
NC/TN border. With only shallow low-level moisture available and
northwest winds quickly shutting down after 06Z Wednesday, only
expect a brief 6 hour window of light snow, with only little to
no accumulation expected Tuesday evening. Overnight lows Tuesday
will run 10-15 degrees below normal as a very cold and dry airmass
advects in and dewpoints plummet. With strong wind gusts in place,
don`t be surprised if a Cold Weather Advisory is needed for portions
of the area as apparent temperatures drop near to below zero in the
northern mountains. Surface high is expected to set up shop across
the central and southern Appalachians by Wednesday and remain
anchored there through Wednesday night before weakening and shifting
offshore the Southeast Coast by Thursday. A weak, positively tilted
shortwave will dig over the Plains on Wednesday and send reinforced
perturbations across the Southeast without much fanfare, but should
tap into the coastal baroclinic zone and induce cyclogenesis over
the Gulf of Mexico. With a Rex Block developing over the West Coast
and the shortwave sinking well south of the area, dry northwest flow
aloft will help keep the CFWA dry through the short term.
Continental Polar airmass Tuesday night and Wednesday will help keep
temperatures well below normal. Good radiational cooling conditions
Wednesday night will lead to overnight lows dropping a few more
degrees compared to Tuesday night. Some moderation in the airmass is
expected Thursday as max insolation will settle over the region and
a weak return flow at the surface commences.
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&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 145 PM EST Monday: Weak upper ridge will move over the
East Coast late Thursday into Friday, leading to better airmass
recovery during this time, but guidance are keying in on our next
system this upcoming weekend, but timing differences and overall
evolution continue to diverge some. Expectation is that this next
system will be all liquid, with the exception of possible freezing
rain/sleet at the onset over the higher elevations before turning
all rain for all of the CFWA. The system will push through the
area and a very stout arctic airmass is shown filtering in behind
and will set the stage for a very cold and dry continental polar
airmass across the CFWA and a good chunk of the Lower 48. Some
northwest flow snow may develop on the backside of the system late
Sunday into the early part of next week along the NC/TN border,
but the main weather headline will be the colder air headed our
way by next week. Temperatures will be within a few degrees of
near-normal values through much of the extended, but signs of
really cold air to come by D7 and beyond.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
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At KCLT and elsewhere: expect dry, VFR conditions to prevail thru
the 00z taf period. The stratocu along the NC/TN border and over
the northern NC mtns will likely linger into the overnight, but
any coverage at KAVL should be minimal. Otherwise, skies should
remain mostly clear for the bulk of the period as a dry cold front
moves south of the fcst area tonight. Winds should favor a NWLY
direction tonight and tomorrow morning and then back to a more WLY
direction tomorrow aftn. Most terminals could see some sporadic,
low-end gusts tomorrow aftn/evening, but confidence was too low to
include in the tafs at this time. At KAVL, winds should remain NWLY
thru the taf period with low-end gusts of roughly 20 kts.

Outlook: Brisk, NWLY winds will likely linger into Wednesday morning
over the NC mountains. Otherwise, expect mostly dry/VFR conditions
thru Friday.
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&&

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

&&

$$

SYNOPSIS...CP
NEAR TERM...JPT/MPR
SHORT TERM...CAC
LONG TERM...CAC
AVIATION...JPT