Winter Weather in Georgia, February 28 to 29, 2020

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
652 AM EST Fri Feb 28 2020

.SYNOPSIS...
A clipper system will bring more mountain snow between now and
Saturday morning, with a few rain showers possible elsewhere. After
that system exits, dry and cool air will settle over the area for
the rest of the weekend. A warm and wet pattern is expected to
return early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 650 AM: Webcams near the TN line are showing flurries/light
snow already falling. Meanwhile, plenty of radar returns upstream
over the TN Valley heading our way. So overall, forecast is on
track. Temps are starting out chilly, and with mid clouds streaming
in right before daybreak, they may have an impact on aftn highs.

As of 330 AM: Precip is starting to blossom on radar mosaic across
the Mid-South, associated with potent vort lobe diving into the
base of deep upper longwave trough. This precip will continue
to expand and shift east, impacting the Southern Appalachians by
late morning. The associated vort lobe will bring steep mid-lvl
lapse rates, resulting in a 100 J/kg or more of sbCAPE. The latest
CAMs agree on convective-looking snow shower activity for the NC
mountains, especially the Smokies, Nantahala and Unicoi mountains
in the west, thanks to a westerly upslope flow. Latest QPF and
snow totals with this activity today thru Saturday morning haven't
changed much from previous forecast. And with confidence increasing
on the totals, have opted to upgrade to a Winter Storm Warning
for Graham and Swain counties above 3500 ft. Also, expanded the
Winter Weather Advisory to Macon and southern Jackson counties
above 3500 ft. The rest of the advisory looks good. Outside of
these areas, expect increasing clouds and isolated to widely
scattered showers. Fcst soundings still show shallow sfc-based
warm layer and some CAPE in the snow-growth zone. So it will be
possible for a few snow and/or graupel showers to develop east of
the mountains, especially the NC foothills and Piedmont. But not
expecting any impacts with temps in the 40s to near 50 deg. Given
the strong forcing and steep lapse rates, this system has the
potential to overperform, like previous events this winter. But
moisture looks a bit more lacking, so confidence is low for any
accumulating snow outside the high elevations today. Another
issue with this feature will be windy conditions. Deep mixing
could tap into gusts approaching 30-35 mph or more this aftn,
especially across the Upstate and NE GA, in addition to the high
elevations. Not expecting winds to warrant an advisory at this
point, but it does bear watching.

Tonight, another strong shortwave will follow right on the heels
of the first one, bringing another round of snow showers to
NC mountains. This second round should be more like a typical
NW flow snow event, as 850 mb flow veers from westerly to
west-northwesterly. CAA ramps up as well, and snow ratios should
become a little better for accumulating snow. However, the event
doesn't last long enough to accumulate warning criteria snow
amounts. Temps will fall into the 20s to lower 30s across the
entire area, which is below normal for the end of February.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 200 AM Fri: Winds will continue to be oriented for continued
upslope flow across the Appalachians on Saturday. However, moisture
will be depleted through the morning, as heights rise across the
region with the arrival of high pressure. While a well defined
shortwave trough will be overhead early in the day, subsidence
inversion should already be setting in; not looking particularly
likely for the shortwave to drive any shower development. Thus, the
fcst reflects the remaining upslope snow tapering off during the
morning. Settled weather can be expected for the rest of the weekend,
with temps moderating from Saturday to Sunday as the sfc high
migrates across the area. By early Monday, the high will be centered
off the East Coast, and low pressure will be traveling north of the
Great Lakes. The resultant southwesterly return flow will pump
moisture inland from the Gulf, mainly across the lower Mississippi
and Ohio valleys, but it is sufficient for PoPs to return Sunday
night to our western mountain zones and adjacent areas near the
south-facing Escarpment.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 300 AM Fri: The northern stream will continue to progress early
next week, as sfc cyclone pushes thru eastern Canada. Meanwhile, the
western Atlantic ridge will more or less block the southern stream,
and phasing of shortwaves subsequently is expected across the central
CONUS, with attendant cyclogenesis. A moist return flow regime thus
looks likely to continue across the Southeast thru the middle of the
week, with warm temps. PoPs will continue for the western zones and
the south-facing Escarpment early in the medium range; the focus for
heavy rainfall around that time most likely will be over the lower
Ohio Valley near a developing warm front. As the aforementioned
trough swings into our area, a marked uptick in precip coverage and
especially rates should occur across the CWA, most likely Wednesday.
The GFS depiction of the phased trough results in a faster and more
vigorous frontal precip event, whereas the Euro and Canadian show the
front languishing over the Southeast and accordingly prog a longer
period of precip lasting into Thursday. PoPs taper off late Thursday
as consensus indicates the system will exit to our east by that
time, as temps fall back again.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
At KCLT and Elsewhere: Plenty of mid clouds streaming across the
area as expected to start the 12z TAFs, with lower-VFR cigs expected
this aftn, as a strong upper wave passes by. Snow showers or RA/SN
shower mix expected in the mountains, which are expected to impact
KAVL, but no significant accum expected. Isolated to scattered
showers will be able to develop east of the mountains during the
aftn hours, especailly in the NC foothills/piedmont. A mix of snow
and/or graupel is possible with these showers, thanks to steep mid-
lvl lapse rates. But sfc temps will be warm. Confidence too low to
mention SN or GR at KCLT (will go with PROB30 for -SHRA for the 12z
TAF). Winds will start out light, but increase out of the SW and
become gusty by midday (toggling to NW at KAVL by 18z). Lower cigs
should clear out, and winds become a little lighter this evening.

Outlook: VFR conditions will generally persist through the weekend,
but with occasional flight restrictions and/or scattered snow
showers possible over the mountains from time to time through
Saturday. Deeper moisture and the potential for more restrictions
returns on Monday and persists thru the middle of next week.

Confidence Table...

            12-18Z        18-24Z        00-06Z        06-12Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High  99%     High  99%     High  96%
KHKY       High 100%     High  98%     High 100%     High 100%
KGMU       High 100%     High  99%     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

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...Winter Weather Advisory until noon EST Saturday for NCZ033-
     048>050-052-059.
     Winter Weather Advisory above 3500 feet until noon EST
     Saturday for NCZ062-063.
     Winter Weather Advisory below 3500 feet until noon EST
     Saturday for NCZ051-058.
     Winter Storm Warning above 3500 feet until noon EST Saturday
     for NCZ051-058.
SC...None.

&&

SYNOPSIS...08
NEAR TERM...ARK
SHORT TERM...08
LONG TERM...08
AVIATION...ARK

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
628 AM EST Fri Feb 28 2020

NCZ051-058-291130-
Swain-Graham-
628 AM EST Fri Feb 28 2020

...WINTER STORM WARNING IN EFFECT UNTIL NOON EST SATURDAY ABOVE
3500 FEET...
...WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON EST SATURDAY BELOW
3500 FEET...

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.
   Winter Storm Warning.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.
   Winter Storm Warning.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to report snow and ice accumulations to our
office.

NCZ033-048>050-052-059-062-063-291130-
Avery-Madison-Yancey-Mitchell-Haywood-Northern Jackson-Macon-
Southern Jackson-
628 AM EST Fri Feb 28 2020

...WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON EST SATURDAY...

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Winter Weather Advisory.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to report snow and ice accumulations to our
office.

GAZ010-017-NCZ053-064-065-291130-
Rabun-Habersham-Buncombe-Transylvania-Henderson-
628 AM EST Fri Feb 28 2020

This Hazardous Weather Outlook is for northeast Georgia and western
North Carolina.

.DAY ONE...Today and tonight.

Snow showers may occur at times across the mountains of western
North Carolina and northeast Georgia today, continuing into early
Saturday. Light accumulations are possible, especially at higher
elevations.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

GAZ018-026-028-029-NCZ035>037-056-057-068>072-082-501>510-SCZ001>014-
019-291130-
Stephens-Franklin-Hart-Elbert-Alexander-Iredell-Davie-Catawba-Rowan-
Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-Union NC-
Caldwell Mountains-Greater Caldwell-Burke Mountains-Greater Burke-
McDowell Mountains-Eastern McDowell-Rutherford Mountains-
Greater Rutherford-Polk Mountains-Eastern Polk-Oconee Mountains-
Pickens Mountains-Greenville Mountains-Greater Oconee-
Greater Pickens-Greater Greenville-Spartanburg-Cherokee-York-
Anderson-Abbeville-Laurens-Union SC-Chester-Greenwood-
628 AM EST Fri Feb 28 2020

This Hazardous Weather Outlook is for northeast Georgia, piedmont
North Carolina, western North Carolina and upstate South Carolina.

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

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