Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
648 PM EST Thu Nov 11 2021

.SYNOPSIS...
A cold front approaching from the west keeps rain chances in the
forecast into tonight. Surface high pressure builds in briefly on
Friday before a reinforcing cold front tracks across the region late
Friday night into early Saturday. Surface high pressure returns
Sunday before a second reinforcing cold front crosses the region
Sunday night. Cool and dry high pressure returns yet again early
next week.

&&

.NEAR TERM /THROUGH FRIDAY/...
As of 645 PM EST Thursday: The forecast is mostly on-track. Some
minor adjustments were made to refine PoPs during the next few
hours, along with bumping up winds during the frontal passage in
line with the latest near-term guidance.  Have generally kept timing
unchanged while incorporating additional detail into prefrontal
showers and postfrontal visibility/sky cover issues.

A broad upper low should continue deepening as it wobbles SE, moving
over the Great Lakes later overnight and tomorrow. As this happens,
the associated frontal zone will become increasingly occluded
as it approaches and moves across the East Coast later today and
into tonight.  Meanwhile, accelerating low-lvl SLY flow responding
to large-scale height falls will allow Gulf of Mexico moisture
to continue advecting into our fcst area thru the afternoon. PoPs
taper to the high to mid chance range across much of the area by
late aftn/early evening. The frontal precip band is then expected
to surge into the southern Appalachians tonight and move fairly
quickly eastward through the overnight hours. Categorical PoPs
are advertised over most areas, although the deeper forcing is
expected to pass north of the area.  This along with a waning
of already-weak instability will likely result in increasing
disorganization of the frontal band as it moves across the higher
terrain this evening. Low-level shear parameters, although still
fairly impressive at around 30 kts in the 0-1 km layer, will
likely be inadequate for a notable high shear/low CAPE severe storm
threat, as model guidance continues to generate little in the way of
sfc-based CAPE (i.e., less than 500 J/kg.) Frontal band should move
east of the area by 11z or so, with rapid clearing from the west
by mid to late morning. The rest of tomorrow will be mostly clear
and dry with high temps expected to rebound back above climatology.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
As of 230 PM EST Thursday: Upper-level troughing will continue
across the eastern CONUS throughout the duration of the short term
period. The first trough will be just off to our west at the
beginning of the forecast period tracking across the CWA early
Saturday morning into early Saturday evening before tracking into
the western Atlantic Saturday night. This trough will drive a
reinforcing cold front across northeast Georgia and the western
Carolinas early Saturday. Stuck with a dry forecast as limited
moisture will be available with this FROPA and as sfc high pressure
is expected to build in quickly behind the departing front. Cloud
cover will mainly increase along the NC/TN border Friday night into
late Saturday morning. Breezy NW'ly winds will develop behind the
cold front Saturday leading to decent CAA and much cooler temps.
Bumped up winds and wind gusts behind the FROPA Saturday in
coordination with neighboring WFOs. Friday night lows will be near
or just above normal. Highs on Saturday should range from near
normal to just below normal east of the mountains and 7 to 15
degrees below normal across the mountains. Saturday night lows will
drop to 5 to 10 degrees below normal thanks to good radiational
cooling.

Sfc high pressure sticks around for Sunday leading to continued cool
and dry conditions. 850 mb flow turns southwesterly Sunday leading to
slightly warmer highs across the mountains compared to Saturday.
High temps on Sunday will be 5 to 10 degrees below climo. Meanwhile,
the second upper-level trough will approach from the northwest
tracking out of the Midwest region. However, the trough axis will
remain just west of the area at the end of the period. This feature
will act to increase cloud cover slightly across the northwestern
zones Sunday.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 230 PM EST Thursday: The upper-level trough will be just west
of the CWA at the start of the extended forecast period. The trough
axis will track across the region Sunday night into Monday dragging
a second reinforcing cold front across northeast Georgia and the
western Carolinas late Sunday night into early Monday morning. This
FROPA will also have limited moisture available. However the extreme
northwestern portions of the NC mtns, (mainly along the NC/TN
border), could see a few snow showers late Sunday night into early
Monday morning. Any snowfall accumulations will be very light. Winds
behind the front will increase leading to a windy day across the
CWA, with the strongest gusts across the higher terrain. At this
time it does not look like wind advisory criteria will be met, even
after bumping up winds and wind gusts. High pressure builds in at
the sfc behind the departing FROPA Monday afternoon and remains the
main weather driver into the middle of the week leading to dry
conditions. Another FROPA is expected to approach the area towards
the end of the extended increasing rain chances again. Low temps
will be below normal Sunday night through Tuesday night becoming
above normal towards end of the period. Highs will be below normal
early next week, becoming near normal to above normal towards the
end of the period.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
At KCLT and elsewhere: Conditions across the Upstate have
been variable the last few hours, with KGSP, KGMU, and KAND
hovering between MVFR and IFR all evening owing to lowered
cigs and poorer-than-anticipated visibility.  KCLT remains VFR,
and should remain so for the next few hours, notwithstanding a
few brief showers rolling across Mecklenburg County before 02Z.
The main frontal band should arrive in the Upstate by 02-03Z,
warranting -SHRA at all sites and a broad area of IFR to LIFR
cigs and MVFR vsbys, essentially affecting all TAF sites by
06Z or so.  Isolated thunder is expected with this frontal
band, but for now does not appear to need mention in the TAFs.
Winds currently southeasterly, but with the frontal passage taking
place after 06Z, flow should shift to more westerly before daybreak.
With the intrusion of dry high pressure behind the front, conditions
should rapidly rebound to VFR at all sites by midmorning.  Clear,
dry weather and light westerly to northwesterly flow should then
persist through the end of the TAF period.

Outlook: Conditions should remain dry and VFR thru Sunday, before
another weak front may produce more active weather and accompanying
restrictions.

&&

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

&&

SYNOPSIS...AP
NEAR TERM...JPT/MPR
SHORT TERM...AP
LONG TERM...AP
AVIATION...MPR

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
517 AM EST Thu Nov 11 2021

GAZ010-017-018-026-028-029-NCZ035>037-056-057-068>072-082-501>510-
SCZ001>014-019-121030-
Rabun-Habersham-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-
517 AM EST Thu Nov 11 2021

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

.DAY ONE...Today and tonight.

A band of showers and possibly a few embedded low-topped
thunderstorms will cross the mountains this evening and the rest of
the area late evening through the overnight. The main threats will be
gusty winds and cloud-to-ground lightning. An isolated damaging wind
gust threat cannot be ruled out as the convection crosses the
Piedmont.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ033-048>053-058-059-062>065-121030-
Avery-Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-Graham-
Northern Jackson-Macon-Southern Jackson-Transylvania-Henderson-
517 AM EST Thu Nov 11 2021

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...Today and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

ARK

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
655 PM EST Thu Nov 11 2021

GAZ010-017-018-120030-
Rabun GA-Stephens GA-Habersham GA-
655 PM EST Thu Nov 11 2021

...Strong thunderstorms will impact portions of western Stephens,
Habersham and south central Rabun Counties through 730 PM EST...

At 654 PM EST, Doppler radar was tracking strong thunderstorms along
a line extending from near Cleveland to 13 miles east of Dahlonega to
4 miles north of Gainesville. Movement was east at 40 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Toccoa, Clarkesville, Cornelia, Baldwin, Demorest, Mount Airy, Alto,
Tallulah Falls, Lake Rabun and Lakemont.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3454 8362 3458 8364 3460 8365 3462 8364
      3465 8366 3468 8364 3471 8364 3479 8340
      3460 8329 3446 8340 3448 8347 3449 8354
      3443 8362 3450 8367
TIME...MOT...LOC 2354Z 258DEG 35KT 3462 8378 3450 8374 3436 8383

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

MOORE