Hail and Damaging Winds in South Dakota, July 21, 2017

Name: Hail and Damaging Winds in South Dakota, July 21, 2017
Start: 2017-07-21T17:24
End: 2017-07-21T23:30
Location: South Dakota

July 21, 2017 · NWS ABR · 22 events in 9 counties and zones

Severe thunderstorms brought large hail up the size of tennis balls along with wind gusts up to 75 mph to parts of north central and northeast South Dakota. Several structures were damaged along with some windows broken.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 22

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.

What happened

The episode as NWS ABR wrote it up.

What forecasters said that day

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 Aberdeen, SD wrote its last area forecast discussion before the first event at Jul 21, 12:57 PM CST, 4 hours 27 minutes earlier.

Area forecast discussion, Jul 21, 12:57 PM CST, 4 hours 27 minutes before

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Hazardous weather outlook, Jul 21, 2:41 PM CST, 2 hours 43 minutes before

Hazardous Weather Outlook...UPDATED
National Weather Service Aberdeen SD
341 PM CDT Fri Jul 21 2017

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-221200-
Traverse-Big Stone-Corson-Campbell-McPherson-Brown-Marshall-
Roberts-Walworth-Edmunds-Day-Dewey-Potter-Faulk-Spink-Clark-
Codington-Grant-Hamlin-Deuel-Stanley-Sully-Hughes-Hyde-Hand-Jones-
Lyman-Buffalo-
341 PM CDT Fri Jul 21 2017 /241 PM MDT Fri Jul 21 2017/

This Hazardous Weather Outlook is for portions of west central
Minnesota, central South Dakota, north central South Dakota, and
northeast South Dakota.

.DAY ONE...This Afternoon and Tonight

Heat: Heat indices will range from 100 to 105 degrees across
central South Dakota eastward into the James River valley into
this evening.

Storms: Strong to severe storms are possible into this evening
over north central and northeast South Dakota and west central
Minnesota. Large hail and strong, damaging winds are possible -
with an enhanced threat for northeast South Dakota into west
central Minnesota. An isolated tornado threat also exists over far
northeast South Dakota into west central Minnesota.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Elevated fire danger will occur across central South Dakota on
Saturday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be necessary through this evening along and
east of the Missouri River.

SRF

The radar

The Aberdeen radar (KABR), 115 km away, was scanning. The volume nearest the first event began at 23:20 UTC.

Open the radar archive at this moment

Event by event

16 thunderstorm wind, 6 hail. Local standard time, as filed.

Thunderstorm Wind, Roberts

When: July 21, 5:24 PM CST
Where: Roberts County, 5.53 mi N of Claire City
Measured: 52 kt (60 mph) estimated gust
Reported by: Public
Coordinates: 45.930, -97.100

Sixty mph winds broke off several large tree branches.

Thunderstorm Wind, Roberts

When: July 21, 6:15 PM CST
Where: Roberts County, 0.69 mi N of New Effington
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 45.860, -96.920

Sixty mph winds were estimated.

Thunderstorm Wind, Corson

When: July 21, 5:50 PM MST
Where: Corson County, 4.8 mi WNW of Mc Laughlin
Measured: 57 kt (66 mph) measured gust
Reported by: Mesonet
Coordinates: 45.850, -100.910

Thunderstorm Wind, Corson

When: July 21, 6:15 PM MST
Where: Corson County, 2.93 mi SSE of Mahto
Measured: 56 kt (64 mph) measured gust
Reported by: Mesonet
Coordinates: 45.730, -100.660

Hail, McPherson

When: July 21, 7:19 PM CST
Where: McPherson County, 12.06 mi SSW of Langlake
Measured: 1 in hail
Reported by: Public
Coordinates: 45.690, -99.320

Hail, Faulk

When: July 21, 7:37 PM CST
Where: Faulk County, 2.13 mi NNE of Wecota
Measured: 1.75 in hail
Reported by: Public
Coordinates: 45.200, -99.110

Hail, Faulk

When: July 21, 7:54 PM CST
Where: Faulk County, 3.13 mi SSE of Wecota
Measured: 2.5 in hail
Reported by: Public
Coordinates: 45.130, -99.090

Thunderstorm Wind, Faulk

When: July 21, 7:54 PM CST
Where: Faulk County, 3.13 mi SSE of Wecota
Measured: 61 kt (70 mph) estimated gust
Reported by: Public
Coordinates: 45.130, -99.090

Seventy mph winds downed a tree along with many large tree branches. The winds combined with tennis ball hail caused damage to windows and crops.

Hail, Walworth

When: July 21, 8:23 PM CST
Where: Walworth County, 4.39 mi NNE of Lowry
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 45.390, -99.940

Hail, Potter

When: July 21, 9:00 PM CST
Where: Potter County, 0.69 mi S of Gettysburg
Measured: 1 in hail
Reported by: Public
Coordinates: 45.010, -99.950

Thunderstorm Wind, Spink

When: July 21, 9:23 PM CST
Where: Spink County, Redfield
Measured: 65 kt (75 mph) estimated gust
Reported by: Emergency Manager
Coordinates: 44.870, -98.520

Winds gusted to over seventy mph in Redfield.

Thunderstorm Wind, Spink

When: July 21, 9:36 PM CST
Where: Spink County, 0.85 mi NW of Tulare
Measured: 65 kt (75 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 44.740, -98.510

A large tree was downed onto a garage causing damage to it.

Thunderstorm Wind, Spink

When: July 21, 9:53 PM CST
Where: Spink County, 3.13 mi SSE of Redfield Arpt
Measured: 61 kt (70 mph) estimated gust
Reported by: Public
Coordinates: 44.810, -98.500

Seventy mph winds knocked down several older or dead trees.

Thunderstorm Wind, Spink

When: July 21, 10:00 PM CST
Where: Spink County, 7.7 mi NE of Brentford
Measured: 52 kt (60 mph) estimated gust
Reported by: Public
Coordinates: 45.230, -98.220

Sixty mph winds were estimated.

Thunderstorm Wind, Spink

When: July 21, 10:23 PM CST
Where: Spink County, 2.76 mi S of Conde
Measured: 65 kt (75 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 45.110, -98.100

Seventy-five mph winds were estimated.

Hail, Hand

When: July 21, 10:33 PM CST
Where: Hand County, 7.11 mi SSW of Ree Hgts
Measured: 0.88 in hail
Reported by: Public
Coordinates: 44.430, -99.270

Thunderstorm Wind, Hand

When: July 21, 10:35 PM CST
Where: Hand County, 0.85 mi NW of Miller Arpt
Measured: 50 kt (58 mph) measured gust
Reported by: Mesonet
Coordinates: 44.530, -98.960

Thunderstorm Wind, Spink

When: July 21, 10:42 PM CST
Where: Spink County, Turton
Measured: 65 kt (75 mph) measured gust
Reported by: Emergency Manager
Coordinates: 45.050, -98.100

Thunderstorm Wind, Hand

When: July 21, 10:45 PM CST
Where: Hand County, 0.85 mi SW of Miller
Measured: 52 kt (60 mph) measured gust
Reported by: Emergency Manager
Coordinates: 44.510, -98.990

Thunderstorm Wind, Hand

When: July 21, 11:10 PM CST
Where: Hand County, 5.49 mi E of Danforth
Measured: 50 kt (58 mph) measured gust
Reported by: Mesonet
Coordinates: 44.240, -98.770

Thunderstorm Wind, Codington

When: July 21, 11:25 PM CST
Where: Codington County, 0.49 mi W of Henry
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 44.880, -97.460

Sixty mph winds were estimated.

Thunderstorm Wind, Codington

When: July 21, 11:30 PM CST
Where: Codington County, 2.08 mi WSW of Grover
Measured: 70 kt (81 mph) estimated gust
Reported by: Public
Coordinates: 44.810, -97.310

Eighty mph winds destroyed a large shed and half of a quonset building.

What these are

Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in South Dakota in 2017 Every state in 2017 This day in weather history Warnings in South Dakota, July 2017

Sources

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 2026-10-01. Each event’s entry at NCEI: 715585, 715591, 715592, 715593, 715579, 715580, 715581, 715586, 715582, 715583, 715594, 715587, 715588, 715595, 715596, 715584, 715597, 715598, 715599, 715600, 715601, 715590.