A cluster of thunderstorms moved across Upstate South Carolina during the late afternoon and evening. Brief damaging winds were reported near Anderson.
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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.
A cluster of thunderstorms moved across Upstate South Carolina during the late afternoon and evening. Brief damaging winds were reported near Anderson.
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 21, 1:51 PM EST, 2 hours 46 minutes earlier.
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
251 PM EDT Tue Aug 21 2018
.SYNOPSIS...
A cold front will move to the Carolina coast on Wednesday.
Expect cool high pressure to pass across the eastern states
Thursday and Friday then move offshore for the weekend. As the upper
trough moves out over the Atlantic this weekend, a hot ridge is
expected to replace it next week. So expect cooler than normal
weather to end this week then hot weather next week.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 245 PM EDT Tuesday: An upper closed low, which is expected to
gradually open as it progresses eastward tonight, continues to push
into the OH Valley this afternoon, as it's associated north to south
oriented cold front is currently positioned across central
Tennessee. Given latest guidance, anticipate the front to reach the
western extent of the FA tonight, pushing through the eastern fringe
by Wednesday morning.
For the rest of today, despite lingering cloud cover through much of
this morning which kept the area a bit more stable than previously
anticipated, scattered showers and thunderstorms are gradually
increasing in coverage as clouds begin to decrease in spots. With
some destabilization and the approaching front from the west
providing additional lift especially into this evening, latest CAM
guidance continues to suggest scattered showers and thunderstorms
through tonight. Weak shear could lead to a few broad rotating
storms, but overall anticipate primary threat to be damaging winds,
as the higher potential for widespread severe weather remains off to
the north. With PWATs nearing two inches, heavy downpours or
localized minor flooding will be possible. Low temperatures tonight
will drop into the upper 60s/low 70s, though cooler across the
mountains.
Overnight, isolated showers will be possible west of the I-77
corridor through into Wednesday morning, with patchy areas of fog
possible across the mountains as the cold front exits the FA off to
the southeast. Have kept low PoPs for isolated showers along the TN
border through Wednesday afternoon with NW flow, while elsewhere,
quiet conditions are expected as drier air infiltrates in. High
temperatures will be around normal.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
As of 250 PM EDT Tuesday: Guidance in good agreement showing a break
in the active weather for at least a couple of days. Upper trough
axis moves east and ridging begins building in from the west. At the
surface, high pressure builds in from the west with deep layer
drying. No convection expected either day. Highs will be nearly
steady around 5 degrees below normal. Lows Thursday morning will be
around 5 degrees below normal but fall to nearly 10 degrees below
normal Friday morning. The cooler temps will also be accompanied by
very comfortable dew points falling into the 50s both days.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 155 PM EDT Tuesday: Starting 00Z Saturday. Cool surface high
pressure moves off the New England coast Friday night and Saturday
but still riding over the Carolinas ahead of a progressive Great
Lakes trough. The easterly flow ahead of the trough will help to
keep temperatures below normal for one last day on Saturday. The
trough moves east of New England on Sunday as a Texas centered 500mb
ridge builds east. This ridge will gradually establish itself over
the SE states through mid week becoming centered somewhere near our
area by Wednesday. This happens as a trough develops over the West
Coast. Some diurnally driven convection can be expected for our area
mainly for the mountains where differential heating will help create
updrafts leading to shower and storm development. Under the gradual
warming effect of the ridge, max temps will rise 2 to 3 degrees each
day in the medium range period. Min temps start just below normal
early Saturday then around or just above normal through first half
of the week.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
At KCLT and elsewhere: With an approaching cold front currently west
of the area, mainly MVFR prevails this afternoon as low cigs
continue to linger much longer than expected, though a few areas are
beginning to scatter out to VFR, while others have briefly
deteriorated to IFR given a SHRA/TSRA moving over the TAF site.
Expect showers and thunderstorms to increase in coverage this
afternoon and tonight as the cold front moves into the area,
bringing periods of IFR heavier downpours/lower cigs and gusts up to
30 kts possible in stronger storms. Per latest guidance, anticipate
coverage of SHRA/TSRA to become isolated in nature overnight,
diminishing with the cold front. Otherwise, SW winds AOB 12 kts will
prevail through the rest of today, gradually veering with the cold
front, beginning across the mountains later tonight, and eventually
at KCLT towards Wednesday morning. Isolated showers will be possible
across the mountains Wednesday morning, which could bring lingering
MVFR/IFR to KAVL. Otherwise, expect VFR.
Outlook: Quiet weather conditions will be in place behind the cold
front as drier air infiltrates in. Thus, expect VFR to prevail
through the end of the week.
Confidence Table...
19-01Z 01-07Z 07-13Z 13-18Z
KCLT High 100% High 100% High 98% High 100%
KGSP High 100% High 100% High 100% High 100%
KAVL High 100% High 96% Low 49% High 84%
KHKY High 98% High 100% High 100% 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 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...SGL
SHORT TERM...RWH
LONG TERM...DEO
AVIATION...SGLHazardous Weather Outlook National Weather Service Greenville-Spartanburg SC 618 AM EDT Tue Aug 21 2018 GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065- 068>072-082-501>510-SCZ001>014-019-221030- 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- 618 AM EDT Tue Aug 21 2018 This Hazardous Weather Outlook is for northeast Georgia, piedmont North Carolina, western North Carolina and upstate South Carolina. .DAY ONE...Today and tonight. A robust cold front will approach the forecast area from the west and help to generate numerous showers and thunderstorms. Some of these storms could become severe and produce large hail and damaging wind gusts. Isolated urban and small stream flooding is also a threat with these storms. The flooding threat will be greatest over the higher terrain. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. No hazardous weather is expected. .SPOTTER INFORMATION STATEMENT... Spotters are requested to forward any reports of large hail, damaging winds, tornadoes, or flash flooding to our office. JPT
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
318 PM EDT TUE AUG 21 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0240 PM FLASH FLOOD 2 SW ASHFORD 35.86N 81.97W
08/21/2018 MCDOWELL NC EMERGENCY MNGR
EMERGENCY MNGR REPORTED US 221 IS FLOODED IN MULTIPLE
LOCATIONS NEAR NORTH COVE AND ASHFORD WITH MULTIPLE
TRIBUTARIES TO THE NORTH FORK CATAWBA RIVER OUT OF THEIR
BANKS. STORM-TOTAL RAINFALL OF 1.5-2.5 INCHES OCCURRED
IN A TWO-HOUR PERIOD.
&&
JMPPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
347 PM EDT TUE AUG 21 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0320 PM FLASH FLOOD SSW ASHFORD 35.87N 81.94W
08/21/2018 MCDOWELL NC OFFICIAL NWS OBS
GAUGE AT NORTH FORK CATAWBA RIVER ABOVE US 221 NE OF
NORTH COVE ROSE ABOVE MINOR FLOOD STAGE TO A LEVEL OF
9.23 FT.
&&
LECSpecial Weather Statement
National Weather Service Greenville-Spartanburg SC
449 PM EDT TUE AUG 21 2018
GAZ026-028-212115-
Hart GA-Franklin GA-
449 PM EDT TUE AUG 21 2018
...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN FRANKLIN AND
SOUTHWESTERN HART COUNTIES UNTIL 515 PM EDT...
At 449 PM EDT, Doppler radar was tracking a strong thunderstorm 5
miles southeast of Carnesville, or over Victoria Bryant State Park,
moving east at 30 mph.
Locations to be impacted include...
Hartwell, Royston, Canon, Franklin Springs, Bowersville, Victoria
Bryant State Park and Vanna.
Wind gusts up to 45 mph and pea size hail will be possible in these
areas.
LAT...LON 3424 8309 3427 8312 3424 8317 3425 8326
3434 8328 3441 8294 3425 8291 3423 8293
TIME...MOT...LOC 2049Z 268DEG 27KT 3430 8318
LANEPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
516 PM EDT TUE AUG 21 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0315 PM TSTM WND DMG 4 NNE LENOIR 35.96N 81.51W
08/21/2018 CALDWELL NC 911 CALL CENTER
911 CALL CENTER REPORTED A TREE DOWN ON ZACKS FORK RD AND
COTTRELL HILL RD. TIME ESTIMATED FROM RADAR.
&&
LECSpecial Weather Statement
National Weather Service Greenville-Spartanburg SC
516 PM EDT TUE AUG 21 2018
GAZ028-SCZ010-212145-
Hart GA-Anderson SC-
516 PM EDT TUE AUG 21 2018
...A CLUSTER OF THUNDERSTORMS WILL IMPACT CENTRAL HART AND ANDERSON
COUNTIES UNTIL 545 PM EDT...
At 516 PM EDT, Doppler radar indicated the leading edge of a cluster
of thunderstorms along a line extending from 5 miles northwest of
Anderson to 3 miles southeast of Hartwell, and moving east at 35 mph.
Locations to be impacted include...
Anderson, Hartwell, Homeland Park, Belton, Williamston, Northlake,
Reed Creek, West Pelzer, Starr and Anderson Airport.
Wind gusts up to 40 mph and pea size hail will be possible in these
areas.
LAT...LON 3434 8302 3464 8279 3466 8246 3464 8245
3462 8245 3460 8243 3457 8242 3431 8261
TIME...MOT...LOC 2116Z 258DEG 30KT 3459 8270 3432 8289
LANEPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
517 PM EDT TUE AUG 21 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0410 PM TSTM WND DMG 5 W TURNERSBURG 35.91N 80.90W
08/21/2018 IREDELL NC 911 CALL CENTER
911 CALL CENTER REPORTED A TREE DOWN ON RIVER RUN RD.
TIME ESTIMATED FROM RADAR.
&&
LECThe Greer radar (KGSP), 53 km away, was scanning. The volume nearest the first event began at 21:38 UTC.
1 thunderstorm wind. Local standard time, as filed.
County comms reported a tree blown down on power lines at the intersection of Snow Rd and Amber Dr and another tree down at Highways 252 and 76.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Carolina in 2018Every state in 2018This day in weather historyWarnings in South Carolina, August 2018
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: 782134.