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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KGSP 011745
AFDGSP

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1245 PM EST Mon Mar 1 2021

.SYNOPSIS...
-- Changed Discussion --
Dry high pressure will build over from the north tonight into
Tuesday. Unsettled weather returns from the west Tuesday night into
Wednesday as low pressure tracks from west to east across the
region. Another low pressure system may affect the Gulf Coast region
Friday into Saturday.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
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As of 1234 pm EST: Radar shows a wide band of light rain moving
into the mtns from east TN, while the precip east of the Blue
Ridge continues to break up. Thus, the higher precip chances shift
to the TN border region through mid-Afternoon, and then the lower
Piedmont as we get the front to push across the fcst area late in
the day. Temps continue to be in a state of flux as precip moves out
to the east, we get some thin patches in the cloud cover, and the
cold advection is delayed. Some rebound has occurred as a result,
but still think the clouds and light precip moving back in from the
west will limit the potential for really warm temps this afternoon.

Otherwise, gusty northwest winds will also develop in the cold
advection through the day, but with gust values remaining below
advisory criteria in the windiest mountain locations where a
secondary, reinforcing cold fropa arrives this afternooon. The
deeper moisture should settle generally southeast of our Piedmont
counties by sundown along with the passing cold front.  Any shallow
upslope moisture into the western mountains will dry up fairly
quickly in the cold air along the spine of the mountains this
evening. So, any isolated snow showers or flurries will be short-
lived and non-accumulating. 1031 mb surface high pressure will then
build over the OH River valley tonight, with chilly thicknesses
spilling southward east of the Appalachians.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 145 AM EST Monday...A split flow pattern aloft will evolve
into a general trof over the period as a srn stream h5 low traverses
the FA Tue night into Wed. A broad offshore sfc low will be
supported by this upper energy and will bring a decent amt of
GOM/Atl moisture to the area beginning Tue afternoon. Meanwhile, a cP
sfc high will track off the midAtl coast and provide a weak insitu
ridge before breaking down Wed morning.

This general pattern will likely support a wintry mix of precip
across the NC mtns Tue night, with light snow transitioning to
freezing rain, then to rain by 15z Wed. The latest NAM soundings
dropped across the NC escarpment show a strong and deep warm nose
interacting with sub-freezing sfc temps abv 3.5 Kft to support
-fzra, while the GFS is notably warmer with llvl partial thicknesses
and indicates more of a sn/ip situation. So, have blended the llvl
thermal profiles and used a top down approach for p/types, which
generated arnd an inch of snow across the higher peaks with perhaps
up to 2 inches over the Smokies. The freezing rain would begin arnd
08z and persist into mid morning with a few hundredths of an inch
favoring the nrn BR escarpment. If these ice amts hold over the next
few fcst cycles, an advisory may be issued. The atmos dries out
during the day Wed as a Canadian high drops south and reinforces a
srn stream sfc high building in from the west thru the period. Max
temps will remain a little below normal each day, while mins hover
arnd or a bit abv normal levels.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 210 AM EST Monday...The ext range fcst looks to remain quite
dry as the models continue to show a suppressed large-scale pattern
over the SE CONUS. Thus, little change was made to the already dry
fcst. A stg subs zone will slowly cross the area, while a couple cP
sfc highs build south and force a favored storm track well south of
the FA each day. With winds generally maintained n/ly and weak CAA
flow in place beginning Thu night, expect max temps to begin the
period Thu abv normal, then cool a little below normal Fri thru Sun.
Dewpoints will drop and mix out each afternoon, which could create
some fire-wx concerns across NE GA based on RH each afternoon,
except Sun when llvl moisture begins to return to the area. Winds
shud remain relatively weak, however, and plenty of sunshine will be
had making for rather nice days for early March.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
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At KCLT and elsewhere: VFR expected at all terminals through the
period. Although radars show a wide band of light precip moving
in from east TN, much of this activity will not make it past the
mtns. Cannot rule out a brief low cloud restriction, possibly even
an MVFR ceiling temporarily at KAVL, think the more westerly flow
will discourage it. East of the mtns, we seem to have settled into a
mid-level broken/overcast ceiling, and that is expected to continue
until after fropa. Wind remains tricky at KCLT. Most likely, the
current SW direction will prevail until late afternoon when the
front finally pushes in from the west. The 21Z time might be too
soon for the shift from WSW to WNW, but as we progress through the
evening, the direction is more and more likely to be northerly. The
rest of the fcst will be just mid/high clouds and the wind direction
veering around the dial. Any low clouds and precip from the next
system will not approach until after the end of the TAF period.

Outlook: Moisture will surge back into the area Tuesday night,
with restrictions and precipitation chances returning through early
Wednesday. Another round of drying is expected by late Wednesday,
likely continuing through the end of the work week.

Confidence Table...

            17-23Z        23-05Z        05-11Z        11-12Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High 100%     High 100%     High 100%
KHKY       High 100%     High 100%     High 100%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     High 100%     High 100%     High 100%

The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables are available at
the following link:

www.weather.gov/gsp/aviation
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...HG
NEAR TERM...HG/PM
SHORT TERM...SBK
LONG TERM...SBK
AVIATION...PM