Winter Storm in Georgia, February 8, 2020

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
643 AM EST Sat Feb 8 2020

.SYNOPSIS...
A fast-moving system will bring chances for rain and some snow to
the area today. Dry conditions will return on Sunday before another
system brings rain chances back Monday and Tuesday. The pattern will
remain unsettled for the rest of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 640 AM EST: The current hazard suite still looks good
given the cold and dry air in place across the region. The main
concern may be a need for expansion of the Advisory if the
precipitation moves in early enough given that the morning
temperatures bottomed out even colder than expected.

Water vapor shows the upstream shortwave now east of the lower MS
River Valley, with radar returns blossoming across northern Alabama.
Generally clear skies and excellent radiating conditions over the
southeast ahead of this system permitted cool and dry air to set up
across the western Carolinas and northeast Georgia. The upstream
wave will bring a short window of robust upper jet divergence, deep-
layer DPVA, and deeper moisture across the forecast area mainly
during the 15Z to 21Z window. The forecast will lean heavily toward
the colder NAM profiles as the operational GFS has been a warm
outlier among the GEFS plumes. Lapse rates will briefly steepen up
as well with the passing wave to boost precip rates at times. Given
this setup, a Winter Storm Warning has been posted across the
northeast GA mountains and Macon County NC, and the surrounding
Winter Weather Advisory now includes Stephens County GA, Oconee and
Pickens Mountains in SC, and the entire Counties from Transylvania
back through the Smokies, including the lower valleys. Accumulations
and snow mix farther east remain somewhat questionable, but light
accums on grassy surfaces are now looking more possible mainly west
of Spartanburg SC, with more of a wet snow/rain mixing over eastern
sections, including I-77/Charlotte. The main lingering question mark
centers around the indicated mid-level drying wrapping into the
picture from the WSW this afternoon. This could undercut ice
nucleation and the associated snow and accums. All told, the outline
of the hazards is highly subject to change on short notice as the
system evolves today.

The wave will move rapidly east this evening, with lingering
precipitation paring back to the typical west to northwest flow
moisture areas before ending overnight. This airmass will support
max temps today some 15 to 20 degrees below climo, with mins 1 to 2
categories below climo tonight.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 145 AM EST Saturday: The short term period begins with a dry
day on Sunday as transient surface high pressure shifts eastward
across the Carolinas. The center of the high is off the Mid-Atlantic
by Monday, with and elongated upper wave/frontal zone advancing
northeastward and encroaching on the area by the afternoon and
evening hours Monday. PWs 2-3 standard deviations above average,
surface convergence, and upper divergence setting up over the far
western Carolinas will set the stage for another substantial
rainfall event as surface waves propagate along this frontal zone. A
strong LL jet is also forecast to develop overnight Monday and cross
the area by Tuesday morning, with the orientation of the surface
frontal boundary setting up a scenario that could encourage heavy
rainfall at times late Monday night through Tuesday morning and the
potential for training of better rainfall rates. Of note are the
extremely wet antecedent conditions (many main stem rivers will
likely remain well above base flow Monday), which turn this from "a
potential heavy rainfall event" to a "concerning chance for heavy
rainfall on top of already saturated ground." The details on exactly
where the axis of heaviest rain may fall will be worked out over the
next couple of days, but this next system will need to be watched
closely.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 250 AM EST Saturday: The stalled frontal boundary and
accompanying rainfall will remain over the forecast area during the
day on Tuesday, though with the surface low pulling away to the
northeast Tuesday night, there will likely be some lull in the
precip through Wednesday morning. A sharper upper disturbance will
move through eastward on Wednesday ahead of an upper trough, with a
surface low pulling northeast off the Gulf coast later Wednesday
afternoon and evening. A warm-front-like feature will activate over
the area around this time, with rain chances ramping up once again
Wednesday evening. Upper support from the approaching trough will
increase Thursday, and a moisture tap from the Gulf of Mexico and
surface convergence/frontogenesis will favor rain that may be heavy
at times. Considering the extremely soggy antecedent conditions,
there may be yet another threat for flooding on Thursday if heavy
rain does materialize. The location and extent of the flood threat
will have an awful lot to do with who sees the heaviest rainfall
earlier in the week, so while the forecast rainfall totals for later
in the work week are concerning, it's still too early to narrow down
the most substantial heavy rain/flood risk for this time frame.
Despite almost constant cloud cover, temperatures will run just
above normal for most the week.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
At KCLT and Elsewhere: A vigorous upper-level shortwave will move
rapidly across the region from the west-southwest today. Given the
cool and dry air in place across the terminal forecast area, some of
the associated precipitation is highly likely to fall as snow -
especially across the NC mountains and the Upstate SC sites, but
also at least briefly at KCLT. High clouds will thicken quickly and
lower through the VFR range this morning, with MVFR setting up under
the developing precipitation this afternoon, and then IFR cigs at
times late in the day. Low stratus and fog could continue well into
the nighttime hours after the deep forcing and moisture clear out
due to lingering surface and boundary layer moisture. Winds will
quickly toggle southerly today, then veer SW and then more westerly
through the period.

Outlook: Drying conditions briefly return on Sunday. A moist frontal
system with probable flight restrictions approaches the area from
the west early next week and could linger through at least mid week.

Confidence Table...

            11-17Z        17-23Z        23-05Z        05-06Z
KCLT       High 100%     High 100%     Low   53%     High  89%
KGSP       High 100%     High  95%     Med   68%     Med   66%
KAVL       High 100%     Med   62%     Med   70%     High  94%
KHKY       High 100%     High 100%     Low   51%     High  89%
KGMU       High 100%     Med   70%     Med   68%     Med   72%
KAND       High 100%     High  86%     High  85%     High  94%

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...Winter Weather Advisory until 7 PM EST this evening for GAZ018.
     Winter Storm Warning until 7 PM EST this evening for GAZ010-
     017.
NC...Winter Weather Advisory until midnight EST tonight for NCZ051-
     052-058.
     Winter Weather Advisory until 7 PM EST this evening for NCZ059-
     063-064.
     Winter Storm Warning until 7 PM EST this evening for NCZ062.
SC...Winter Weather Advisory until 7 PM EST this evening for SCZ001-
     002.

&&

SYNOPSIS...17
NEAR TERM...HG
SHORT TERM...17
LONG TERM...17
AVIATION...HG

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
328 AM EST Sat Feb 8 2020

GAZ026-028-029-NCZ048>050-053-065-505>510-SCZ003>007-010>012-019-
090830-
Franklin-Hart-Elbert-Madison-Yancey-Mitchell-Buncombe-Henderson-
McDowell Mountains-Eastern McDowell-Rutherford Mountains-
Greater Rutherford-Polk Mountains-Eastern Polk-Greenville Mountains-
Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg-
Anderson-Abbeville-Laurens-Greenwood-
328 AM EST Sat Feb 8 2020

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

.DAY ONE...Today and tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Another storm system will bring heavy rainfall to the area late
Monday night through Tuesday morning. Up to an additional 2-3 inches
of rain could fall on already saturated ground, increasing the risk
for flooding.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ051-052-058-090830-
Swain-Haywood-Graham-
328 AM EST Sat Feb 8 2020

...WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT EST TONIGHT...

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...Sunday through Friday.

Another storm system will bring heavy rainfall to the area late
Monday night through Tuesday morning. Up to an additional 2-3 inches
of rain could fall on already saturated ground, increasing the risk
for flooding.

.SPOTTER INFORMATION STATEMENT...

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

GAZ018-NCZ059-063-064-SCZ001-002-090830-
Stephens-Northern Jackson-Southern Jackson-Transylvania-
Oconee Mountains-Pickens Mountains-
328 AM EST Sat Feb 8 2020

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 7 PM EST THIS EVENING...

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

Another storm system will bring heavy rainfall to the area late
Monday night through Tuesday morning. Up to an additional 2-3 inches
of rain could fall on already saturated ground, increasing the risk
for flooding.

.SPOTTER INFORMATION STATEMENT...

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

GAZ010-017-NCZ062-090830-
Rabun-Habersham-Macon-
328 AM EST Sat Feb 8 2020

...WINTER STORM WARNING IN EFFECT UNTIL 7 PM EST THIS EVENING...

This Hazardous Weather Outlook is for northeast Georgia and 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 Storm Warning.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Another storm system will bring heavy rainfall to the area late
Monday night through Tuesday morning. Up to an additional 2-3 inches
of rain could fall on already saturated ground, increasing the risk
for flooding.

.SPOTTER INFORMATION STATEMENT...

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

LEC

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
345 AM EST Sat Feb 8 2020

GAZ026-028-NCZ033-048>050-053-065-501>510-SCZ003>007-010-082100-
Franklin-Hart-Avery-Madison-Yancey-Mitchell-Buncombe-Henderson-
Caldwell Mountains-Greater Caldwell-Burke Mountains-Greater Burke-
McDowell Mountains-Eastern McDowell-Rutherford Mountains-
Greater Rutherford-Polk Mountains-Eastern Polk-
Greenville Mountains-Greater Oconee-Greater Pickens-
Greater Greenville-Spartanburg-Anderson-
Including the cities of Royston, Gumlog, Lavonia,
Franklin Springs, Canon, Hartwell, Nuberg, Reed Creek, Ingalls,
Banner Elk, Newland, Faust, Mars Hill, Marshall, Walnut,
Allenstand, Hot Springs, Luck, Swiss, Burnsville, Celo,
Micaville, Ramseytown, Busick, Spruce Pine, Poplar, Asheville,
Hendersonville, Fletcher, Dana, East Flat Rock, Tuxedo, Etowah,
Patterson, Kings Creek, Lenoir, Sawmills, Granite Falls,
Jonas Ridge, Morganton, Pleasant Grove, Valdese, Ashford,
Sugar Hill, Woodlawn, Old Fort, Marion, Nebo, Dysartsville, Fero,
Glenwood, Chimney Rock State Park, Forest City, Rutherfordton,
Spindale, Saluda, Tryon, Columbus, Mill Spring, Tigerville,
Gowensville, Cleveland, Slater-Marietta, Seneca, Oakway, Easley,
Dacusville, Clemson, Greenville, Taylors, Greer, Mauldin,
Fork Shoals, Simpsonville, Berea, Spartanburg, and Anderson
345 AM EST Sat Feb 8 2020

...SPOTTY LIGHT SNOW ACCUMULATIONS POSSIBLE TODAY ACROSS PORTIONS
OF THE WESTERN CAROLINAS AND NORTHEAST GEORGIA...

A low pressure system moving rapidly across the region today will
interact with the chilly airmass in place to produce light snow
at times. Accumulations will be possible by the afternoon, with a
half inch of snow in the mountain valleys to nearly 2 inches
along the higher mountain ridges, and a dusting to a half inch in
several locations across Upstate South Carolina, northeast
Georgia, and the North Carolina foothills. Accumulations would
mainly affect grassy and elevated surfaces, but light
accumulations are possible on colder road surfaces such as
bridges and overpasses.

Most locations will see temperatures climb above freezing today,
but likely stay locked in the 30s. Significant travel impacts are
not expected, but a few locations could see temperatures hover
near the freezing mark for a good part of the day. A few slippery
spots could develop on area roadways, especially in the central
and northern mountains, and across the western North Carolina
foothills.

HG