Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
228 PM EDT Sat Aug 7 2021

.SYNOPSIS...
As an upper level disturbance moves off the East Coast tonight,
drier high pressure builds into the area Sunday.  This will bring
the return of typical summertime weather across the region through
the start of the week. Moisture and the chances for showers and
thunderstorms return for the middle of the week.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of 228 PM: Scattered/numerous showers and storms have
developed over the mtns/foothills this afternoon, as predicted,
as a mid/upper trof axis moves overhead. The environment has
sfc-based CAPE on the order of 1500-2500 J/kg, which will be
sufficient to fuel additional storms. Shear is modest at best,
but probably enough to afford some weak organization into the
late afternoon, especially if some outflows can consolidate off
the higher terrain. The mesoanalysis shows just enough dCAPE
above 800 J/kg to make the storms interesting, so a few
strong/severe outflow winds will not be ruled out. Chances will
diminish this evening diurnally and as a shortwave axis passes
east. Precipitable water has not tailed off as quick as
expected, and storm motion vectors are fairly short, so we can't
rule out additional excessive rainfall.

After the upper trof passes later this evening, sky should clear
and wind should go light/variable as high pressure settles over
the mtns, setting up a good potential for fog development in the
pre-dawn hours, particularly where rain falls this afternoon. Low
temps will be about a category below normal. Sunday should be a
fairly quiet day with weak high pressure hanging around. High temps
will be right around normal for early August. In the absence of
anything to actively discourage convection, we should see widely
scattered showers over the mtns and foothills in the afternoon.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
As of 100 PM EDT Saturday...Upper ridging dominates across the FA
thru the short term as an h5 trof approaches yet attenuates across
ern TN by Tue. With a classic Atl sfc ridge config, winds will align
generally sw/ly thru the period and maintain high td/s and allow
for weak temp adv within the BL. This will generate low-end sbCAPE
values arnd 1000 J/kg breaking a mlvl cap each afternoon wihin very
weak column flow. Thus, expect diurnally driven pulse and outflow
driven storms each afternoon, a few a which may briefly become quite
strong. Max and min temps will remain arnd normal each day.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 145 PM EDT Saturday...The ext range continues to show good
confidence in the overall pattern. Expect subTrop ridging to
dominate with any sigfnt upper waves remaining well north of the FA.
This will continue normal summertime wx over the region with similar
fcsts for each day. Little column flow along with skinny sbCAPE
depicted by the models, will lead to non/organized thunderstorms
each afternoon with increasing PWATS as a weak sfc front settles in
from the NW. With slow moving or perhaps anchored storms, there may
be some localized hydro issues, mainly confined to the mtns where
the better chance of deep convec is likely. Surface td/s will remain
high and along with temps at or a little abv normal, expect muggy
conds each day.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
At KCLT and Elsewhere...Prevailing VFR outside of thunderstorms
through the evening hours. First concern is thunderstorm activity
associated with an upper trof. Storms already developed over the
mtns will affect KAVL first, then will move east of the Blue Ridge
during the late afternoon/early evening. Will employ a TEMPO to
handle the associated restrictions. The storms should end by 01Z at
the latest. Clearing sky this evening, combined with light winds,
will set up a fog scenario in the pre-dawn hours tonight. Visibility
will probably drop lowest in places that experience rainfall late
today. For the time being, prevailing MVFR visibility will be used
as a placeholder starting from 06Z to 08Z. We will eventually add
a TEMPO group at some locations for possible IFR/LIFR conditions
as confidence increases. The fog should burn off quickly Sunday
morning, after which only scattered low clouds are expected with
a light wind. A few showers are possible Sunday afternoon, but
the chances are too low to mention at this time.

Outlook: Diurnal shower/thunderstorm activity will return for
the first part of next week. Fog and low stratus will be possible
each morning, particularly over the mtn valleys and areas primed
by rainfall from the previous evening.

Confidence Table...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       High  99%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High  94%     High 100%
KAVL       High 100%     High 100%     Med   71%     High  88%
KHKY       High 100%     High 100%     High  95%     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

&&

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

&&

SYNOPSIS...DEO
NEAR TERM...PM
SHORT TERM...SBK
LONG TERM...SBK
AVIATION...PM

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
336 PM EDT Sat Aug 7 2021

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-081945-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Avery-Alexander-
Iredell-Davie-Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-Catawba-
Rowan-Graham-Northern Jackson-Macon-Southern Jackson-Transylvania-
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-Oconee Mountains-
Pickens Mountains-Greenville Mountains-Greater Oconee-
Greater Pickens-Greater Greenville-Spartanburg-Cherokee-York-
Anderson-Abbeville-Laurens-Union SC-Chester-Greenwood-
336 PM EDT Sat Aug 7 2021

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

.DAY ONE...This afternoon and tonight.

Scattered to numerous showers and thunderstorms will impact the
western Carolinas and northeast Georgia late this afternoon through
early this evening. Locally heavy rainfall and isolated flooding will
be the primary threat. However, these thunderstorms will also be
capable of producing dangerous lightning, small hail, and very gusty
to damaging winds.

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

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

HG

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
247 PM EDT Sat Aug 7 2021

NCZ068-501>506-508-071930-
McDowell Mountains NC-Greater Rutherford NC-Caldwell Mountains NC-
Burke Mountains NC-Cleveland NC-Greater Burke NC-Greater Caldwell NC-
Eastern McDowell NC-
247 PM EDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of McDowell,
northeastern Rutherford, southern Caldwell, northwestern Cleveland
and Burke Counties through 330 PM EDT...

At 246 PM EDT, Doppler radar was tracking a strong thunderstorm 6
miles northeast of Marion, or over Lake James State Park, moving
southeast at 20 mph.

HAZARD...Winds in excess of 40 mph and up to 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...
Lenoir, Morganton, Marion, Sawmills, Granite Falls, Valdese,
Gamewell, Hudson, Icard and Cajah's Mountain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3586 8134 3582 8134 3533 8176 3562 8221
      3597 8184 3596 8181 3598 8179
TIME...MOT...LOC 1846Z 307DEG 16KT 3573 8190

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

JPT

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
255 PM EDT Sat Aug 7 2021

NCZ065-509-510-SCZ003-006-007-071945-
Henderson NC-Polk Mountains NC-Eastern Polk NC-
Greenville Mountains SC-Spartanburg SC-Greater Greenville SC-
255 PM EDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of southeastern
Henderson, southern Polk, northeastern Greenville and northwestern
Spartanburg Counties through 345 PM EDT...

At 255 PM EDT, Doppler radar was tracking a strong thunderstorm 5
miles west of Columbus, or near Saluda, moving southeast 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...
Columbus, Flat Rock, Landrum, Inman, Tryon, Campobello, Saluda, Lake
Bowen, Tigerville and Lyman.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3521 8197 3519 8197 3518 8194 3492 8217
      3520 8251 3538 8234
TIME...MOT...LOC 1855Z 307DEG 15KT 3523 8230

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

JPT

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
314 PM EDT Sat Aug 7 2021

GAZ026-028-029-072000-
Elbert GA-Hart GA-Franklin GA-
314 PM EDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of central Franklin,
northwestern Elbert and Hart Counties through 400 PM EDT...

At 314 PM EDT, Doppler radar was tracking a strong thunderstorm 4
miles east of Carnesville, or near Canon, moving southeast at 15 mph.

HAZARD...Winds in excess of 40 mph and pea 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...
Hartwell, Carnesville, Royston, Lavonia, Bowman, Canon, Franklin
Springs, Bowersville, Victoria Bryant State Park and Gumlog.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3418 8310 3423 8308 3427 8312 3424 8317
      3425 8321 3434 8335 3449 8315 3436 8282
      3434 8279 3430 8278 3411 8300
TIME...MOT...LOC 1914Z 307DEG 15KT 3438 8316

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

JPT

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
335 PM EDT Sat Aug 7 2021

NCZ068>070-504-506-508-SCZ008-072015-
Greater Rutherford NC-Gaston NC-Cleveland NC-Lincoln NC-
Greater Burke NC-Eastern McDowell NC-Cherokee SC-
335 PM EDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of southeastern
McDowell, Rutherford, western Lincoln, Cleveland, northwestern
Gaston, southwestern Burke and northwestern Cherokee Counties through
415 PM EDT...

At 334 PM EDT, Doppler radar was tracking a strong thunderstorm 10
miles north of Forest City, or 7 miles north of Bostic, moving
southeast at 40 mph.

HAZARD...Winds in excess of 40 mph and up to 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...
Shelby, Forest City, Rutherfordton, Lincolnton, Morganton,
Cherryville, Spindale, Boiling Springs NC, Glen Alpine and Belwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3561 8151 3557 8153 3557 8143 3547 8125
      3508 8175 3547 8213 3562 8201 3576 8180
TIME...MOT...LOC 1934Z 311DEG 35KT 3548 8181

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

JPT

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
347 PM EDT Sat Aug 7 2021

NCZ508>510-SCZ003-007-008-072030-
Greater Rutherford NC-Polk Mountains NC-Eastern Polk NC-Cherokee SC-
Greenville Mountains SC-Spartanburg SC-
347 PM EDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of southwestern
Rutherford, Polk, northeastern Greenville, northern Spartanburg and
northwestern Cherokee Counties through 430 PM EDT...

At 347 PM EDT, Doppler radar was tracking a strong thunderstorm 8
miles east of Columbus, or 7 miles northeast of Landrum, moving
southeast at 30 mph.

HAZARD...Winds in excess of 40 mph and small 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...
Spartanburg, Columbus, Gaffney, Boiling Springs SC, Landrum, Cowpens,
Wellford, Inman, Mayo and Roebuck.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3481 8196 3520 8235 3535 8228 3542 8214
      3522 8176 3518 8177 3518 8169 3513 8160
TIME...MOT...LOC 1947Z 305DEG 28KT 3522 8207

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

JPT

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
406 PM EDT Sat Aug 7 2021

NCZ033-048>050-053-501-503-505-506-072045-
Buncombe NC-McDowell Mountains NC-Yancey NC-Caldwell Mountains NC-
Burke Mountains NC-Eastern McDowell NC-Avery NC-Madison NC-
Mitchell NC-
406 PM EDT Sat Aug 7 2021

...A strong thunderstorm will impact portions of central McDowell,
northeastern Madison, Mitchell, west central Caldwell, southern
Avery, northeastern Buncombe, Yancey and northwestern Burke Counties
through 445 PM EDT...

At 405 PM EDT, Doppler radar was tracking a strong thunderstorm over
Burnsville, moving southeast at 35 mph.

HAZARD...Winds in excess of 40 mph and pea 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...
Spruce Pine, Burnsville, Marion, Mars Hill, Old Fort, Bakersville,
Crossnore, Linville Falls, B.R. Parkway-Craggy To Little Switzerland
and B.R. Parkway-Little Switzerland To Linville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3612 8214 3611 8213 3611 8208 3595 8166
      3578 8192 3576 8192 3554 8222 3590 8270
      3599 8261 3597 8261 3595 8256 3601 8246
      3609 8240 3614 8229 3613 8225 3615 8222
TIME...MOT...LOC 2005Z 305DEG 32KT 3592 8229

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

JPT