Several clusters of thunderstorms developed across the mountains and foothills of South Carolina during the evening and moved east. One of these clusters produced a brief downburst in the Greenville area.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS GSP wrote it up.
Several clusters of thunderstorms developed across the mountains and foothills of South Carolina during the evening and moved east. One of these clusters produced a brief downburst in the Greenville area.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Greenville-Spartanburg, SC wrote its last area forecast discussion before the first event at Aug 4, 9:47 PM EST, 45 minutes earlier.
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1047 PM EDT Fri Aug 4 2017
.SYNOPSIS...
A cold front will cross our area tonight and become stationary from
central Georgia to eastern North Carolina Saturday night. This front
will then return north as a warm front Sunday and Sunday night as
low pressure passes from Texas across the Ohio Valley. The front
will become stationary again across our region for much of the week,
with deep moisture and periods of heavy rain likely.
&&
.NEAR TERM /THROUGH SATURDAY/...
As of 1030 pm: The pre-frontal band of heavy rain showers and
embedded thunderstorms is generally stretched along the I-85
corridor late this evening. Instability has started to wane for all
but the southern tier of the forecast area, but hydro concerns will
likely continue for the Upstate past midnight as the heavy rainfall
orients itself a bit more west to east in the westerly steering
flow. The heavy rain band should gradually wind down as it slips
southeast ahead of the slowly passing cold front through the early
morning hours Saturday. Fog and low clouds could develop both in
areas seeing heavy rainfall, and also in moist westerly upslope into
the mountains overnight. Expect mins to run near to just above climo.
Even though the boundary will settle near, or southeast of, our
southern tier on Saturday, the moisture gradient across the boundary
will be sufficiently broad such that positive buoyancy is progged to
develop from roughly the NC/SC border southward. Diurnal frontal
convection should primarily be focused south of our area, but a
slight chance is nevertheless warranted southeast of I-85.
Meanwhile, instability should be sufficient to fire some isolated
cells across the southern Blue Ridge, and slight chances will be
carried across the southern mtns as well as the southern NC and SC
foothills. Max temps should again fall just shy of climo.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
As of 215 PM Friday: An upper wave will cross the Central Plains and
into the Mid-MS Valley Saturday night thru Sunday, possibly being
enhanced by an MCS. This wave will then shear out within confluent
quasi-zonal flow over the OH Valley to the Mid-Atlantic Sunday night
thru Monday. At the sfc, a stalled front will lift back north as a
warm front, but will be fairly weak. Guidance has slowed down the
return of moisture atop the front thru the day on Sunday, so PoPs
were tweaked downward, especially across the northern half of the
CWFA. As for severe threat, guidance shows limited overlap of CAPE
and bulk shear. So threat should be low. A wavy front roughly
parallel to the upper level flow will set up across the Mid-South to
the OH Valley. Persistent SWLY flow atop the CWFA on the south side
of this boundary will provide plenty of moisture for convection on
Monday. So will have PoPs ramp up to high-end CHC to likely along
the west-facing slopes. Max temps will be near to slightly below
normal and mins near normal both days.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 155 PM Fri: Beginning Monday evening, the cold front drifts
south into our area from Tennessee then becomes nearly stationary
roughly from west to east across the deep south to the Carolinas.
The front remains this way through the remainder of the forecast.
Precipitable water values will be around 2 inches and at times above
that, especially from Wednesday through Friday. This prolonged
period of high Pwats with a stationary front to focus convection
will result in concerns for potential flooding which will increase
as the ground becomes saturated. A broad 500mb trough remains over
the East with shortwaves rotating SE from the upper Plains states to
our region then NE off the New England coast. This will periodically
enhance rainfall as surface low pressures move along the front over
our area. As a result of the thick cloud cover and periods of rain,
max temperatures are trending downward. Looks like Wednesday may be
the coolest as forecast highs from northeast Georgia to Charlotte
are in the lower 80s and this may be too high given the saturation
of the atmosphere. Overall max temperatures several degrees below
normal and Min temperatures near normal or even slightly above given
the thick clouds. There may also be periods of late night and early
morning fog to deal with as dew points and temperatures match
yielding 100% RH.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
At KCLT: The main convective band should settle southeast of KCLT by
04Z, with any lingering showers gradually dissipating through 06Z.
Drier air will start to filter in from the NW toward daybreak, but
abundant low level moisture could lead to overnight low cloud
restrictions just as the surface cold front approaches from the
west. Winds should toggle NW around daybreak Saturday with fropa,
with mainly NW flow and VFR conditions through the day as the
morning low clouds scatter. SW winds will turn NW overnight through
Saturday.
Elsewhere, convection appears done from KAVL to KHKY even though the
surface cold front remains just to the west. Thunderstorms will
continue at the Upstate TAF sites through about 04Z, with showers
lingering through 06Z. The heavy rainfall could lead to low cloud
restrictions at times through daybreak. Lower stratus is also quite
possible in the moist W to NW low level flow reaching KAVL overnight
into Saturday morning. Drier air will continue to filter into the
region from the west behind the front through Saturday with any
lingering low clouds dissipating and conditions VFR throughout. SW
winds this evening will become NW overnight, toggling back to WSW or
SW at Upstate sites on Saturday.
Outlook: The cold front will settle southeast of the terminal area
through Saturday night. Moisture will then steadily return over the
front back into the region Sunday through Monday. Unsettled
conditions will set up through at least the middle of the week as
the boundary remains nearby and moisture pools overhead as a series
of upper level waves pass by. Restrictions will be possible with any
showers or thunderstorms, and fog and low clouds will be possible
each morning around daybreak, mainly in the mtn valleys, but also in
areas that receive heavy rainfall the day before.
Confidence Table...
02-08Z 08-14Z 14-20Z 20-00Z
KCLT High 97% Med 70% High 97% High 100%
KGSP High 100% High 95% High 100% High 100%
KAVL Med 70% Low 39% High 94% High 100%
KHKY High 100% High 93% High 100% High 100%
KGMU High 100% High 96% High 100% High 100%
KAND High 100% High 94% 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 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...DEO
NEAR TERM...HG
SHORT TERM...ARK
LONG TERM...DEO
AVIATION...HGHazardous Weather Outlook National Weather Service Greenville-Spartanburg SC 1051 PM EDT Fri Aug 4 2017 GAZ010-017-NCZ033-035>037-048>053-056-058-059-062>065-068>070- 501>510-SCZ001>003-060300- Rabun-Habersham-Avery-Alexander-Iredell-Davie-Madison-Yancey- Mitchell-Swain-Haywood-Buncombe-Catawba-Graham-Northern Jackson- Macon-Southern Jackson-Transylvania-Henderson-Cleveland-Lincoln- Gaston-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- 1051 PM EDT Fri Aug 4 2017 This Hazardous Weather Outlook is for the mountains of northeast Georgia, the mountains and foothills of western North Carolina, and the Upstate South Carolina mountains. .DAY ONE...Tonight. No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Saturday through Thursday. ..Saturday...No hazardous weather is expected at this time. ..Sunday...No hazardous weather is expected at this time. ..Monday...No hazardous weather is expected at this time. ..Tuesday...No hazardous weather is expected at this time. ..Wednesday...No hazardous weather is expected at this time. ..Thursday...No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... None. GAZ018-026-028-029-NCZ057-071-072-082-SCZ004>014-019-060300- Stephens-Franklin-Hart-Elbert-Rowan-Mecklenburg-Cabarrus-Union- Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg- Cherokee-York-Anderson-Abbeville-Laurens-Chester-Greenwood- 1051 PM EDT Fri Aug 4 2017 This Hazardous Weather Outlook is for northeast Georgia, piedmont North Carolina and upstate South Carolina. .DAY ONE...Tonight. Scattered to numerous showers and thunderstorms will produce locally heavy rainfall across the region into the early morning hours before ending. Isolated flooding of low-lying and poor drainage areas may develop. A few thunderstorms will produce briefly gusty winds as well. .DAYS TWO THROUGH SEVEN...Saturday through Thursday. ..Saturday...No hazardous weather is expected at this time. ..Sunday...No hazardous weather is expected at this time. ..Monday...No hazardous weather is expected at this time. ..Tuesday...No hazardous weather is expected at this time. ..Wednesday...No hazardous weather is expected at this time. ..Thursday...No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotters are asked to relay any reports of flooding or damaging winds to the National Weather Service. HG
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
923 PM EDT FRI AUG 4 2017
SCZ008-009-050215-
York SC-Cherokee SC-
923 PM EDT FRI AUG 4 2017
...STRONG THUNDERSTORMS WITH INTENSE LIGHTNING WILL IMPACT
NORTHWESTERN YORK AND NORTHERN CHEROKEE COUNTIES UNTIL 1015 PM EDT...
At 923 PM EDT, Doppler radar indicated strong thunderstorms with
intense lightning along a line extending from 9 miles southeast of
Shelby to 8 miles southwest of Gaffney, and moving east at 35 mph.
Locations to be impacted include...
Gaffney, York, Clover, Town Of Lake Wylie, Blacksburg, Sharon,
Hickory Grove, Smyrna, Kings Mountain State Park and Cherokee Falls.
In addition to intense lightning, wind gusts up to 45 mph and pea
size hail will be possible in these areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
Frequent lightning is occurring with these storms. If outdoors, try
to get indoors or into a hard topped vehicle. Otherwise, stay away
from open areas and isolated high objects such as trees. When
indoors, stay away from windows and doors and avoid using wired
electronic devices. Do not take a shower or bath. Try to unplug
unnecessary appliances before the storms approach.
&&
LAT...LON 3509 8106 3493 8135 3504 8181 3505 8181
3517 8155 3515 8105 3513 8105 3511 8103
TIME...MOT...LOC 0123Z 276DEG 29KT 3519 8143 3500 8178
CDGSpecial Weather Statement
National Weather Service Greenville-Spartanburg SC
926 PM EDT FRI AUG 4 2017
SCZ006>008-050230-
Cherokee SC-Spartanburg SC-Greater Greenville SC-
926 PM EDT FRI AUG 4 2017
...STRONG THUNDERSTORMS WITH INTENSE LIGHTNING WILL IMPACT EAST
CENTRAL GREENVILLE...CENTRAL SPARTANBURG AND CENTRAL CHEROKEE
COUNTIES UNTIL 1030 PM EDT...
At 926 PM EDT, Doppler radar indicated strong thunderstorms with
intense lightning along a line extending from 10 miles northwest of
Gaffney to 6 miles north of Greenville Downtown, and moving east at
20 mph.
Locations to be impacted include...
Spartanburg, Gaffney, Greer, Boiling Springs SC, Travelers Rest,
Duncan, Lyman, Cowpens, Wellford and Inman.
In addition to intense lightning, wind gusts up to 45 mph and pea
size hail will be possible in these areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
Frequent lightning is occurring with these storms. If outdoors, try
to get indoors or into a hard topped vehicle. Otherwise, stay away
from open areas and isolated high objects such as trees. When
indoors, stay away from windows and doors and avoid using wired
electronic devices. Do not take a shower or bath. Try to unplug
unnecessary appliances before the storms approach.
&&
LAT...LON 3496 8248 3513 8194 3503 8149 3499 8148
3484 8193
TIME...MOT...LOC 0126Z 286DEG 19KT 3515 8182 3495 8241
CDGSpecial Weather Statement
National Weather Service Greenville-Spartanburg SC
931 PM EDT FRI AUG 4 2017
SCZ002-003-005>007-010-050215-
Pickens Mountains SC-Greater Pickens SC-Anderson SC-
Greenville Mountains SC-Spartanburg SC-Greater Greenville SC-
931 PM EDT FRI AUG 4 2017
...STRONG THUNDERSTORMS WITH INTENSE LIGHTNING WILL IMPACT CENTRAL
GREENVILLE...WEST CENTRAL SPARTANBURG...NORTH CENTRAL ANDERSON AND
PICKENS COUNTIES UNTIL 1015 PM EDT...
At 930 PM EDT, Doppler radar indicated strong thunderstorms with
intense lightning along a line extending from 12 miles north of
Greenville Downtown to 8 miles west of Pickens, and moving southeast
at 25 mph.
Locations to be impacted include...
Greenville Downtown, Easley, Pickens, Greenville Eastside, West
Greenville, Greer, Mauldin, Taylors, Berea and Five Forks.
In addition to intense lightning, wind gusts up to 40 mph and pea
size hail will be possible in these areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
Frequent lightning is occurring with these storms. If outdoors, try
to get indoors or into a hard topped vehicle. Otherwise, stay away
from open areas and isolated high objects such as trees. When
indoors, stay away from windows and doors and avoid using wired
electronic devices. Do not take a shower or bath. Try to unplug
unnecessary appliances before the storms approach.
&&
LAT...LON 3490 8291 3490 8290 3491 8290 3492 8291
3494 8290 3495 8290 3495 8291 3496 8292
3506 8243 3485 8190 3469 8263
TIME...MOT...LOC 0130Z 312DEG 23KT 3503 8240 3493 8285
CDGSpecial Weather Statement
National Weather Service Greenville-Spartanburg SC
1003 PM EDT FRI AUG 4 2017
NCZ071-082-SCZ009-014-050300-
Union NC-Mecklenburg NC-York SC-Chester SC-
1003 PM EDT FRI AUG 4 2017
...STRONG THUNDERSTORMS WITH INTENSE LIGHTNING WILL IMPACT SOUTHERN
MECKLENBURG...NORTHWESTERN UNION...NORTH CENTRAL CHESTER AND YORK
COUNTIES UNTIL 1100 PM EDT...
At 1003 PM EDT, Doppler radar indicated strong thunderstorms with
intense lightning along a line extending from 7 miles west of Uptown
Charlotte to 3 miles northwest of York to 12 miles southeast of
Gaffney, and moving southeast at 20 mph.
Locations to be impacted include...
Rock Hill, York, Monroe, South Charlotte, Southwest Charlotte,
Matthews, Indian Trail, Weddington, Fort Mill and Stallings.
In addition to intense lightning, wind gusts up to 40 mph will be
possible in these areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
Frequent lightning is occurring with these storms. If outdoors, try
to get indoors or into a hard topped vehicle. Otherwise, stay away
from open areas and isolated high objects such as trees. When
indoors, stay away from windows and doors and avoid using wired
electronic devices. Do not take a shower or bath. Try to unplug
unnecessary appliances before the storms approach.
&&
LAT...LON 3489 8079 3494 8078 3508 8091 3501 8091
3492 8086 3490 8088 3484 8087 3483 8090
3481 8090 3473 8129 3494 8149 3498 8148
3503 8127 3515 8107 3512 8048
TIME...MOT...LOC 0203Z 303DEG 20KT 3522 8097 3502 8128 3498 8147
CDGSpecial Weather Statement
National Weather Service Greenville-Spartanburg SC
1019 PM EDT FRI AUG 4 2017
NCZ057-071-072-082-050300-
Rowan NC-Union NC-Cabarrus NC-Mecklenburg NC-
1019 PM EDT FRI AUG 4 2017
...STRONG THUNDERSTORMS WITH INTENSE LIGHTNING WILL IMPACT
CABARRUS...CENTRAL MECKLENBURG...SOUTHEASTERN ROWAN AND NORTHEASTERN
UNION COUNTIES UNTIL 1100 PM EDT...
At 1018 PM EDT, Doppler radar indicated strong thunderstorms with
intense lightning along a line extending from 3 miles northeast of
Salisbury to 3 miles southeast of Downtown Concord to 5 miles south
of Uptown Charlotte, and moving southeast at 30 mph.
Locations to be impacted include...
Downtown Concord, Salisbury, Uptown Charlotte, Southwest Charlotte,
East Charlotte, Mint Hill, Harrisburg, Spencer, Granite Quarry and
Rockwell.
In addition to intense lightning, wind gusts up to 40 mph will be
possible in these areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
Frequent lightning is occurring with these storms. If outdoors, try
to get indoors or into a hard topped vehicle. Otherwise, stay away
from open areas and isolated high objects such as trees. When
indoors, stay away from windows and doors and avoid using wired
electronic devices. Do not take a shower or bath. Try to unplug
unnecessary appliances before the storms approach.
&&
LAT...LON 3550 8030 3519 8051 3516 8044 3517 8039
3518 8037 3517 8036 3520 8028 3511 8029
3513 8096 3539 8061 3578 8049 3577 8047
3573 8045 3572 8038 3572 8034 3571 8032
3568 8033 3558 8021 3555 8021 3551 8018
TIME...MOT...LOC 0218Z 295DEG 24KT 3570 8044 3537 8054 3515 8086
CDGSpecial Weather Statement
National Weather Service Greenville-Spartanburg SC
1042 PM EDT FRI AUG 4 2017
SCZ003-005>007-050345-
Greater Pickens SC-Greenville Mountains SC-Spartanburg SC-
Greater Greenville SC-
1042 PM EDT FRI AUG 4 2017
...THUNDERSTORMS WITH INTENSE LIGHTNING AND TORRENTIAL RAINFALL WILL
IMPACT NORTHEASTERN GREENVILLE...NORTHWESTERN SPARTANBURG AND EAST
CENTRAL PICKENS COUNTIES UNTIL 1145 PM EDT...
At 1042 PM EDT, Doppler radar indicated thunderstorms with intense
lightning and torrential rainfall along a line extending from 12
miles south of Columbus to 4 miles west of Pickens, and moving east
at 10 mph.
Locations to be impacted include...
Greenville Downtown, Easley, Pickens, West Greenville, Greer,
Taylors, Berea, Welcome, Boiling Springs SC and Travelers Rest.
Very heavy rainfall rates up to 2 inches per hour will be possible in
these areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
Frequent lightning is occurring with these storms. If outdoors, try
to get indoors or into a hard topped vehicle. Otherwise, stay away
from open areas and isolated high objects such as trees. When
indoors, stay away from windows and doors and avoid using wired
electronic devices. Do not take a shower or bath. Try to unplug
unnecessary appliances before the storms approach.
&&
LAT...LON 3485 8281 3509 8222 3507 8188 3481 8247
3482 8248 3480 8252
TIME...MOT...LOC 0242Z 271DEG 13KT 3507 8225 3486 8279
CDGThe Greer radar (KGSP), 22 km away, was scanning. The volume nearest the first event began at 03:31 UTC.
1 thunderstorm wind. Local standard time, as filed.
SCHP reported multiple trees blown down on the west side of Greenville.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Carolina in 2017Every state in 2017This day in weather historyWarnings in South Carolina, August 2017
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 720904.