Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
304 PM EDT Mon Aug 19 2019

.SYNOPSIS...
An area of low pressure and elevated moisture will persist across
the western Carolinas and northeast Georgia through Wednesday. A
moist cold front will approach the region Thursday and become
stationary on Friday. The front will gradually settle south of the
area through the weekend as high pressure builds in from the north
and maintains cooler than normal temperatures.

&&

.NEAR TERM /THROUGH TUESDAY/...
As of 255 PM EDT Monday: Situated in between a ridge of
high pressure both to the west and east, as a few upper shortwaves
swing through overhead, an unsettled weather pattern has already
blossomed across the western Carolinas and northeast Georgia this
afternoon. With temperatures currently in the upper 80s/lower 90s
and dewpoints in the lower 70s, latest mesoanalysis depicts sbCAPE
values of 2000-3500 J/kg across the area, with plenty of dry air in
place at the mid levels. Thus, would not entirely rule out a few of
these storms becoming strong to severe before the end of the day,
with microbursts, as noted in previous discussions, as a
possibility. In addition, with the aforementioned temperatures and
dewpoints, though below heat advisory criteria, heat indices in the
mid to upper 90s outside the mountains will continue through this
evening.

Expect convection to linger into the evening hours, gradually waning
into tonight, though a few light showers overnight could not be
entirely ruled out. With the expectation of mid to high level clouds
overhead through the overnight hours as weak sfc low meanders north
into the area, expect min temperatures to remain above normal. Some
of the guidance/fcst soundings continued to suggest fog development
towards daybreak on Tuesday, but confidence is fairly low attm given
anticipated cloud cover.

A similar pattern is expected on Tuesday, though the potential for
strong to severe storms will be slightly less. Temperatures will
remain just above normal, with heat indices in the low to mid 90s.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
As of 1:35 PM EDT Monday: the short-term forecast picks up at 00z on
Wednesday with our region stuck between upper ridging to the west and
weaker upper ridging over the Western Atlantic. On Wed, broad upper
trofing begins to dig down across the Great Lakes as the ridges amplify
on either side of us. On Thurs, the upper trof persists over the Great
Lakes as heights fall over our area and upper-lvl flow strengthens
from the west. At the sfc, the Bermuda High will continue to be the
main driver of our synoptic pattern thru most of the period, keeping
a moist, tropical airmass over the CWFA. On Thurs, a moist cold front
will make its way southeastward from the Ohio River Valley and approach
the fcst area early Thurs. The front is expected to move through the
CWFA late Thurs and into early Fri. No major changes were needed for
the sensible fcst with above climatology PoPs each day, with Thurs
carrying likely PoPs across roughly the northern half of the CWFA.
Instability will be decent each day/evening, with little in the way
of shear on Wed and a bit more on Thursday as the front approaches.
Instability will probably be limited to some extent on Thursday as
cloud cover is expected to increase thru the day. Temperatures will
remain just above normal.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 115 PM EDT Monday: An slow moving cold front will continue
pushing over the FA to begin the ext range. With the upper flow
becoming more diffuse the front will become broad and stall while
slowly drifting south thru Fri. Good agreement is seen in the latest
guidance in developing a 1024 mb Canadian high over the Midwest
early Fri and traversing it east thru the period and this shud setup
a wedge scenario across the FA thru the weekend.

In the meantime...good instability will be had along and ahead of
the sfc bndry which will instigate deep tstms. Deep layered
shear remains quite low however...so the mode will likely remain
pulsey with multicellular lines probable into the evening. The
latest GFS is the quickest with bringing in ne/ly flow within
the sfc-h8 layer Fri afternoon at KHKY and then arnd 00z at
KGSP. The other op models are much slower with the wedge idea
development arnd 12z Sat. So...some uncertainty is had with the
onset time of more stable air and a general decrease in thunder
activity Fri evening.

The wedge does look to become mature by Sat afternoon tho and expect
Atl and GOM moisture adv to reinforce the pattern...which could
linger into Mon per the GFS. Max temps on Fri will be right arnd
normal...then below normal temps by a couple cats or so over the
weekend. PoPs will remain abv normal outside the mtns in isentropic
lift...with the wedge bndry likely become convectively active across
the extreme ern to sw/rn zones each afternoon Sat and Sun.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
At KCLT and elsewhere: VFR prevails at all TAF sites this afternoon,
with convection already blossoming across the entire forecast area.
Thus, all TAF sites have prevailing VCSH/VCTS for the afternoon
hours, with TEMPO groups to account for possible short-lived flight
restrictions due to any SHRA/TSRA that moves over a TAF site. Expect
convection to wane into tonight, with lingering mid to high level
clouds and light winds. Latest fcst soundings continue to suggest
the potential for stratus, while some are hinting at fog
development. Confidence is low in regards to fog given the
anticipated cloud cover, but attm, could not entirely rule it out
towards daybreak.

Outlook: The potential for afternoon/evening showers and
thunderstorms is expected to increase throughout the week, as a cold
front approaches from the NW into Thursday. Morning fog and low
stratus will be possible each day across the mountain valleys.
Otherwise, expect VFR.

Confidence Table...

            19-01Z        01-07Z        07-13Z        13-18Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High  94%
KAVL       High 100%     High 100%     Med   68%     High  96%
KHKY       High 100%     High 100%     High  93%     High 100%
KGMU       High 100%     High 100%     High 100%     High  90%
KAND       High 100%     High 100%     High  92%     High  90%

The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:

www.weather.gov/gsp/aviation

&&

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

&&

SYNOPSIS...SBK
NEAR TERM...SGL
SHORT TERM...JPT
LONG TERM...SBK
AVIATION...SGL

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
432 AM EDT Mon Aug 19 2019

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-200845-
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-
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-Chester-Greenwood-
432 AM EDT Mon Aug 19 2019

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

.DAY ONE...Today and tonight.

Scattered thunderstorms are expected to develop across the area this
afternoon, especially near the eastern escarpment of the Blue Ridge
Mountains. Cloud-to-ground lightning, brief heavy downpours, and
locally gusty winds will be the primary threats with these
thunderstorms. A few of the storms may be strong enough to produce
damaging wind gusts.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to forward any reports of large hail,
damaging winds, or flash flooding to our office.

HG

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
349 PM EDT Mon Aug 19 2019

SCZ001-002-192015-
Pickens Mountains SC-Oconee Mountains SC-
349 PM EDT Mon Aug 19 2019

...A STRONG THUNDERSTORM WILL IMPACT WEST CENTRAL PICKENS AND
NORTHEASTERN OCONEE COUNTIES UNTIL 415 PM EDT...

At 349 PM EDT, Doppler radar was tracking a strong thunderstorm 5
miles west of Pickens, or 4 miles north of Six Mile. This storm was
nearly stationary.

Locations to be impacted include...
Devils Fork State Park, Lake Keowee, Keowee Toxaway State Park and
Nine Times.

Wind gusts up to 55 mph and nickel size hail will be possible in
these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of gusty winds and saturated soil conditions will
cause scattered trees and power lines to fall. Seek shelter inside an
interior room.

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

This storm may intensify, so be certain to monitor local radio and tv
stations, as well as local cable tv outlets for additional
information and possible warnings from the National Weather Service.

&&

LAT...LON 3496 8296 3495 8275 3488 8276 3485 8281
      3482 8295
TIME...MOT...LOC 1949Z 094DEG 2KT 3488 8281

Carroll

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
356 PM EDT Mon Aug 19 2019

NCZ509-510-192030-
Polk Mountains NC-Eastern Polk NC-
356 PM EDT Mon Aug 19 2019

...A STRONG THUNDERSTORM WILL IMPACT POLK COUNTY UNTIL 430 PM EDT...

At 355 PM EDT, Doppler radar was tracking a strong thunderstorm near
Columbus. This storm was nearly stationary.

Locations to be impacted include...
Columbus, Tryon, Mill Spring, Green Creek and Lake Adger.

Wind gusts up to 55 mph and nickel size hail will be possible in
these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of gusty winds and saturated soil conditions will
cause scattered trees and power lines to fall. Seek shelter inside an
interior room.

Dime to nickel size hail can cause considerable damage to vehicles.
Consider moving vehicles to a covered storage area before the storm
arrives.

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3535 8208 3534 8208 3534 8207 3519 8201
      3520 8234 3537 8228 3538 8227
TIME...MOT...LOC 1955Z 094DEG 2KT 3524 8214

Carroll

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
406 PM EDT Mon Aug 19 2019

SCZ006-007-192030-
Spartanburg SC-Greater Greenville SC-
406 PM EDT Mon Aug 19 2019

...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL GREENVILLE AND
CENTRAL SPARTANBURG COUNTIES UNTIL 430 PM EDT...

At 406 PM EDT, Doppler radar was tracking a strong thunderstorm 8
miles west of Spartanburg, or near Wellford, moving southwest at 10
mph.

Locations to be impacted include...
Spartanburg, Greer, Boiling Springs SC, Duncan, Lyman, Wellford,
Inman, USC Upstate, Croft State Park and Cedar Springs.

Wind gusts up to 55 mph and nickel size hail will be possible in
these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of gusty winds and saturated soil conditions will
cause scattered trees and power lines to fall. Seek shelter inside an
interior room.

Dime to nickel size hail can cause considerable damage to vehicles.
Consider moving vehicles to a covered storage area before the storm
arrives.

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3492 8230 3505 8228 3506 8222 3510 8222
      3505 8184 3486 8183
TIME...MOT...LOC 2006Z 028DEG 7KT 3498 8208

Carroll

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
409 PM EDT Mon Aug 19 2019

NCZ068-508-192045-
Greater Rutherford NC-Cleveland NC-
409 PM EDT Mon Aug 19 2019

...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL RUTHERFORD AND
NORTHWESTERN CLEVELAND COUNTIES UNTIL 445 PM EDT...

At 409 PM EDT, Doppler radar was tracking a strong thunderstorm 11
miles northwest of Shelby, or near Polkville, moving south at 10 mph.

Locations to be impacted include...
Belwood, Lawndale, Fallston, Polkville, Ellenboro, Casar, Kingstown
and Sunshine.

Wind gusts up to 55 mph and nickel size hail will be possible in
these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Dime to nickel size hail can cause considerable damage to vehicles.
Consider moving vehicles to a covered storage area before the storm
arrives.

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

This storm may intensify, so be certain to monitor local radio and tv
stations, as well as local cable tv outlets for additional
information and possible warnings from the National Weather Service.

&&

LAT...LON 3549 8183 3555 8157 3539 8146 3531 8178
TIME...MOT...LOC 2009Z 340DEG 8KT 3543 8166

Carroll

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
413 PM EDT Mon Aug 19 2019

SCZ002-005-006-010-192045-
Pickens Mountains SC-Greater Pickens SC-Anderson SC-
Greater Greenville SC-
413 PM EDT Mon Aug 19 2019

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL GREENVILLE...NORTH
CENTRAL ANDERSON AND CENTRAL PICKENS COUNTIES UNTIL 445 PM EDT...

At 413 PM EDT, Doppler radar was tracking a strong thunderstorm 4
miles northeast of Easley, or near Berea, moving east at 10 mph.

Locations to be impacted include...
Greenville Downtown, Easley, Pickens, West Greenville, Berea,
Welcome, Powdersville, Liberty, Six Mile and Paris Mountain State
Park.

Wind gusts up to 55 mph and nickel size hail will be possible in
these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

The combination of gusty winds and saturated soil conditions will
cause scattered trees and power lines to fall. Seek shelter inside an
interior room.

Dime to nickel size hail can cause considerable damage to vehicles.
Consider moving vehicles to a covered storage area before the storm
arrives.

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3478 8288 3479 8288 3480 8289 3481 8289
      3481 8290 3486 8290 3497 8285 3495 8237
      3475 8241
TIME...MOT...LOC 2013Z 290DEG 9KT 3485 8252

Carroll

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
421 PM EDT Mon Aug 19 2019

NCZ071-072-192045-
Cabarrus NC-Mecklenburg NC-
421 PM EDT Mon Aug 19 2019

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN CABARRUS AND NORTH
CENTRAL MECKLENBURG COUNTIES UNTIL 445 PM EDT...

At 421 PM EDT, Doppler radar was tracking a strong thunderstorm 4
miles southwest of Huntersville, moving west at 15 mph.

Locations to be impacted include...
Huntersville, Downtown Concord, Kannapolis, West Concord, Cornelius,
Davidson, Charlotte Motor Speedway, Coddle Creek Reservoir, Ramsey
Creek Park and Northeast Charlotte.

Wind gusts up to 55 mph and nickel size hail will be possible in
these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Gusty winds can blow down trees that are dead, or that have weakened
root systems. Outdoor furniture and similar items can be tossed
around if not anchored. Seek shelter indoors.

Dime to nickel size hail can cause considerable damage to vehicles.
Consider moving vehicles to a covered storage area before the storm
arrives.

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

This storm may intensify, so be certain to monitor local radio and tv
stations, as well as local cable tv outlets for additional
information and possible warnings from the National Weather Service.

&&

LAT...LON 3531 8047 3534 8092 3550 8093 3551 8092
      3547 8046
TIME...MOT...LOC 2021Z 089DEG 12KT 3538 8090

Carroll