Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1105 AM EDT Wed Sep 8 2021

.SYNOPSIS...
A cold front is expected to cross our area from the northwest later
today into early Thursday and bring more widespread showers and
thunderstorms to the region. Drying high pressure will spread back
over the region in the front's wake and linger through the weekend
and into the first half of next week, while summertime conditions
make a return to the area as well.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1050 am: Morning convective cluster has moved east of the
forecast area as of late morning. Brief subsident regime and
relatively stable air mass in its wake should result in a lull in
convection for at least the next couple of hours. Nevertheless,
skies are clearing rather quickly in the wake of the convection, and
isolated-to-widely scattered convection should redevelop over the
forecast area by mid-afternoon as the atmosphere destabilizes to the
tune of 2000-3000 J/kg. Through the daytime hours, the primary
impetus for convective initiation will be terrain effects/
differential heating, as it's looking increasingly likely that the
frontal zone to our west will not begin to move into the forecast
area until this evening. Nevertheless, as the flow aloft becomes
increasingly cyclonic and moderate-to-strong instability develops,
PoPs in the 40-60% range appear prudent in most locations.

Deep-lyr shear still looks minimal wrt its potential to organized
storms, however, 0-3 km shear in the 15-25 kt range will probably be
enough to support clustering of cells along cold pools. Strong
downbursts will be possible with any clusters, as well as with
single cell pulse storms. The degree of instability and relatively
low freezing levels will also support marginally severe hail with
the strongest updrafts.

With the front expected to cross the forecast area overnight, some
degree of convective coverage will persist, probably through the end
of the period, and this supports continuation of at least slight
chance PoPs in most areas through 12Z Thursday. Temps are expected
to be a few degrees above normal through the period.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 115 AM EDT Wednesday: The frontal zone is expected to be
in the far eastern CFWA during the beginning portions of the
short-term. Leftover moisture along the boundary may warrant an
early morning shower or thunderstorm along and east of the I-77
corridor, but dry air advection behind the fropa will lead to
much drier conditions during the day Thursday as high pressure
slowly builds in from the west. The upper trough over the Great
Lakes and OH Valley will help push the frontal boundary eastward
as the axis of the upper trough slips past the CFWA Thursday
evening. The sfc pressure gradient tightens up slightly Thursday
into Thursday night and could lead to low-end breezy conditions,
especially in the High Country, but any wind gusts should subside
by Friday morning as the center of the sfc high sets up shop
over the central Appalachians. Mostly sunny and dry conditions will
prevail through Friday as a result. Anomalously lower thicknesses
will keep temperatures in check with near-normal values expected
through the forecast period for highs and a category below normal
for lows as good radiational cooling processes will be in store for
both Thursday and Friday nights.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 215 AM EDT Wednesday: Sfc high will hold steady over the
Mid-Atlantic Saturday, while sliding offshore by Sunday. This
will allow for a return flow to enter back into the CFWA, along
with rising heights from a deepening upper ridge over the central
CONUS. A warming and more humid trend will prevail in this set up
through the period, but the additional subsidence aloft will help
cap any shower and thunderstorm development through the early part
of next week. The next frontal boundary is shown encroaching the
area by the middle part of next week, according to the GFS. Model
guidance keep this away from the CFWA through the day seven, so
most of the extended will remain dry. There are some differences in
the global models. The GFS sags the frontal boundary with height
falls towards the area by next Wednesday and Thursday, while the
ECMWF develops a sub-tropical ridge over the Mid-Atlantic region
and keeps any type of frontal zone far north and west. Either way,
the CFWA will remain mostly dry while temperatures uptick slightly
each day as we introduce another round of summertime conditions
during the medium range.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
At KCLT and Elsewhere: We've been seeing some robust convective
cells develop over our southern Upstate zones, and some activity
coming up from the SW and moving into our NE Georgia zones. Sct
convection will likely continue through the mid-morning hours.
Signals remain mixed wrt the potential for early morning fog/low
stratus, but any breaks in the clouds could permit LIFR conditions
to develop quickly over the mtn valleys and around KAVL. Winds
will be mainly light and SLY to SWLY for the bulk of the period,
but with an uptick in speed to about 10kt with some low-end gusts
this afternoon. I kept the PROB30s for convective chances for
the afternoon/evening hours with the approach of the front from
the NW. Most of the precip should be moving east of our fcst area
as the taf period ends at 06z.

Outlook: Generally fair weather and high pressure is expected
on Thursday in the wake of the frontal passage. The fair wx will
likely persist thru the weekend and into early next week. Mtn
valley fog and low stratus will remain possible each morning.

&&

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

&&

SYNOPSIS...CAC
NEAR TERM...JDL/JPT
SHORT TERM...CAC
LONG TERM...CAC
AVIATION...JPT

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
622 AM EDT Wed Sep 8 2021

GAZ010-017-018-026-028-029-NCZ033-048>053-058-059-062>064-SCZ001-002-
004-005-010>012-019-091030-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Avery-Madison-Yancey-
Mitchell-Swain-Haywood-Buncombe-Graham-Northern Jackson-Macon-
Southern Jackson-Transylvania-Oconee Mountains-Pickens Mountains-
Greater Oconee-Greater Pickens-Anderson-Abbeville-Laurens-Greenwood-
622 AM EDT Wed Sep 8 2021

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

.DAY ONE...Today and tonight.

Scattered showers and thunderstorms will develop this afternoon and
evening. The main threats will be cloud-to-ground lightning, heavy
downpours, and gusty winds.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ035>037-056-057-065-068>072-082-501>510-SCZ003-006>009-013-014-
091030-
Alexander-Iredell-Davie-Catawba-Rowan-Henderson-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-Greenville Mountains-Greater Greenville-
Spartanburg-Cherokee-York-Union SC-Chester-
622 AM EDT Wed Sep 8 2021

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

.DAY ONE...Today and tonight.

Strong to severe thunderstorms will be possible this afternoon and
evening. The main threats will be cloud-to-ground lightning, damaging
winds, and isolated large hail.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
100 PM EDT Wed Sep 8 2021

NCZ065-081730-
Henderson NC-
100 PM EDT Wed Sep 8 2021

...A strong thunderstorm will continue to impact portions of
northern Henderson County through 130 PM EDT...

At 1259 PM EDT, Doppler radar was tracking a strong thunderstorm 8
miles northwest of Hendersonville, or over Mills River. This storm
was moving slowly east.

HAZARD...Winds in excess of 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Hendersonville, Mills River, Fletcher, Mountain Home, Asheville
Airport, Forge Mountain and Horse Shoe.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3533 8245 3535 8263 3540 8265 3544 8260
      3543 8257 3544 8255 3544 8254 3543 8255
      3542 8254 3543 8253 3545 8253 3545 8246
TIME...MOT...LOC 1659Z 250DEG 4KT 3539 8257

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

CSH

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
152 PM EDT Wed Sep 8 2021

NCZ082-081815-
Union NC-
152 PM EDT Wed Sep 8 2021

...A strong thunderstorm will impact portions of southern Union
County through 215 PM EDT...

At 152 PM EDT, Doppler radar was tracking a strong thunderstorm 8
miles northeast of Lancaster, or 5 miles east of Andrew Jackson State
Park, moving northeast at 15 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Waxhaw, Mineral Springs, Jaars and Trinity.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3482 8056 3482 8080 3494 8078 3495 8079
      3496 8040
TIME...MOT...LOC 1752Z 215DEG 12KT 3484 8071

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
155 PM EDT Wed Sep 8 2021

SCZ002-081830-
Pickens Mountains SC-
155 PM EDT Wed Sep 8 2021

...A strong thunderstorm will impact portions of northern Pickens
County through 230 PM EDT...

At 155 PM EDT, Doppler radar was tracking a strong thunderstorm 9
miles northwest of Pickens, or near Jocassee Gorges, moving southeast
at 10 mph.

HAZARD...Winds in excess of 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Keowee Toxaway State Park, Table Rock State Park, Jocassee Gorges,
Lake Jocassee, Lake Keowee, Sunset, Pumpkintown, Sassafras Mountain,
Nine Times and Rocky Bottom.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3492 8291 3494 8290 3497 8292 3499 8294
      3501 8293 3501 8291 3503 8291 3507 8286
      3508 8282 3506 8276 3505 8275 3505 8273
      3499 8256 3495 8259 3489 8274 3484 8283
TIME...MOT...LOC 1755Z 302DEG 9KT 3497 8283

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

CSH

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
212 PM EDT Wed Sep 8 2021

SCZ001-081845-
Oconee Mountains SC-
212 PM EDT Wed Sep 8 2021

...A strong thunderstorm will impact portions of central Oconee
County through 245 PM EDT...

At 211 PM EDT, Doppler radar was tracking a strong thunderstorm 5
miles northwest of Walhalla, or 4 miles southwest of Oconee State
Park, moving east at 10 mph.

HAZARD...Winds in excess of 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Walhalla, Salem, Oconee State Park, Lake Keowee and Mountain Rest.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3490 8319 3491 8318 3490 8295 3476 8297
      3468 8306 3474 8324
TIME...MOT...LOC 1811Z 282DEG 9KT 3481 8313

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

ARK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
214 PM EDT WED SEP 8 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0138 PM     HAIL             4 NNE DANA              35.38N 82.35W
09/08/2021  E1.00 INCH       HENDERSON          NC   PUBLIC

            DIME TO QUARTER SIZED HAIL FOR ABOUT 5 MINUTES. VERY
            LITTLE WIND. ABOUT ONE MILE SOUTH OF EDNEYVILLE.

&&

OUTLAW

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
215 PM EDT Wed Sep 8 2021

NCZ082-081900-
Union NC-
215 PM EDT Wed Sep 8 2021

...Strong thunderstorms will impact portions of Union County through
300 PM EDT...

At 215 PM EDT, Doppler radar was tracking a strong thunderstorm 7
miles southwest of Monroe, or near Mineral Springs, moving northeast
at 15 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Monroe, Indian Trail, Weddington, Unionville, Wesley Chapel, Wingate,
Waxhaw, Lake Park, Mineral Springs and Hemby Bridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3482 8050 3482 8080 3505 8076 3506 8074
      3517 8050 3511 8029 3510 8029
TIME...MOT...LOC 1815Z 218DEG 12KT 3492 8063

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

CSH