Tornadoes and Flash Flood in South Dakota, July 23, 2010

Name: Tornadoes and Flash Flood in South Dakota, July 23, 2010
Start: 2010-07-23T18:04
End: 2010-07-23T22:15
Location: South Dakota

July 23, 2010 · NWS FSD · 34 events in 16 counties and zones

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: $1.1 million
Crop damage: None recorded
Events: 34

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 FSD wrote it up.

Thunderstorms produced large hail, damaging winds, and brief tornadoes in southeast South Dakota during the evening of July 23rd. The storms moved east and affected the area mainly near and south of Interstate 90. However, the storms affected an area further north, including Brookings, when they arrived near the eastern border of South Dakota. Flash flooding resulted in the Brookings area.

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 Sioux Falls, SD wrote its last area forecast discussion before the first event at Jul 23, 2:10 PM CST, 3 hours 54 minutes earlier.

Area forecast discussion, Jul 23, 2:10 PM CST, 3 hours 54 minutes before

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Hazardous weather outlook, Jul 23, 10:09 AM CST, 7 hours 55 minutes before

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The radar

The Aberdeen radar (KABR), 202 km away, was scanning. The volume nearest the first event began at 00:05 UTC.

Open the radar archive at this moment

Event by event

22 thunderstorm wind, 7 hail, 3 tornado, 1 funnel cloud, 1 flash flood. Local standard time, as filed.

Hail, Brule

When: July 23, 6:04 PM CST
Where: Brule County, 0.69 mi S of (9v9)chamberlain Arp
Measured: 1 in hail
Reported by: Law Enforcement
Coordinates: 43.760, -99.320

Thunderstorm Wind, Brule

When: July 23, 6:06 PM CST
Where: Brule County, 0.69 mi N of Chamberlain Arpt
Measured: 70 kt (81 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.810, -99.320

Thunderstorm winds caused tree damage, including several trees blown down.

Hail, Brule

When: July 23, 6:16 PM CST
Where: Brule County, 1.65 mi ESE of (9v9)chamberlain Arp
Measured: 1.75 in hail
Reported by: Trained Spotter
Coordinates: 43.760, -99.290

Funnel Cloud, Gregory

When: July 23, 6:44 PM CST
Where: Gregory County, 4.09 mi SW of Lucas
Reported by: Storm Chaser
Coordinates: 43.240, -99.280

Tornado, Brule

When: July 23, 6:52 PM CST to 6:53 PM CST
Where: Brule County, 14.44 mi ESE of Eagle to 14.54 mi ESE of Eagle
Rating: EF0
Path length: 0.1 mi
Path width: 50 yd
Reported by: Trained Spotter
Coordinates: 43.520, -98.800

A brief tornado caused no reported damage.

Thunderstorm Wind, Charles Mix

When: July 23, 6:53 PM CST
Where: Charles Mix County, 6.3 mi N of Platte Muni Arpt
Measured: 56 kt (64 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.490, -98.840

Thunderstorm winds caused tree damage, including branches blown down. The winds were accompanied by heavy rain and small hail.

Tornado, Gregory

When: July 23, 6:55 PM CST to 6:56 PM CST
Where: Gregory County, 8.18 mi NNW of Bonesteel to 8.13 mi NNW of Bonesteel
Rating: EF0
Path length: 0.15 mi
Path width: 50 yd
Reported by: Law Enforcement
Coordinates: 43.180, -99.010

A brief rope like tornado caused no reported damage.

Tornado, Gregory

When: July 23, 6:58 PM CST to 6:59 PM CST
Where: Gregory County, 4.54 mi ENE of Herrick to 4.72 mi ENE of Herrick
Rating: EF0
Path length: 0.2 mi
Path width: 50 yd
Reported by: Trained Spotter
Coordinates: 43.150, -99.100

A brief tornado caused no reported damage.

Thunderstorm Wind, Douglas

When: July 23, 7:15 PM CST
Where: Douglas County, 0.69 mi N of Harrison
Measured: 61 kt (70 mph) estimated gust
Reported by: Law Enforcement
Coordinates: 43.440, -98.530

Thunderstorm winds caused tree damage, including large trees blown down. One healthy maple tree was uprooted.

Hail, Aurora

When: July 23, 7:23 PM CST
Where: Aurora County, 0.85 mi SW of Plankinton
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 43.710, -98.490

Thunderstorm Wind, Douglas

When: July 23, 7:25 PM CST
Where: Douglas County, 0.5 mi W of Corsica
Measured: 61 kt (70 mph) estimated gust
Property damage: $10,000
Reported by: Law Enforcement
Coordinates: 43.420, -98.410

Thunderstorm winds blew down and flattened one grain bin and damaged several others. The winds also caused tree damage, including several trees blown down.

Hail, Aurora

When: July 23, 7:26 PM CST
Where: Aurora County, 5.73 mi NNE of Stickney
Measured: 1.75 in hail
Reported by: Trained Spotter
Coordinates: 43.660, -98.400

Large hail caused an unknown amount of crop damage. The hail was accompanied by damaging winds.

Thunderstorm Wind, Aurora

When: July 23, 7:26 PM CST
Where: Aurora County, 5.73 mi NNE of Stickney
Measured: 52 kt (60 mph) estimated gust
Reported by: Storm Chaser
Coordinates: 43.660, -98.400

Thunderstorm winds contributed to an unknown amount of crop damage. The winds were accompanied by large hail.

Hail, Charles Mix

When: July 23, 7:30 PM CST
Where: Charles Mix County, 0.69 mi S of Pickstown
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 43.060, -98.530

Thunderstorm Wind, Davison

When: July 23, 7:45 PM CST
Where: Davison County, 0.85 mi NW of Mitchell
Measured: 61 kt (70 mph) estimated gust
Property damage: $25,000
Reported by: Broadcast Media
Coordinates: 43.730, -98.030

Thunderstorm winds caused tree and power line damage, including several trees blown down. A house was damaged by a tree falling onto its roof.

Thunderstorm Wind, Davison

When: July 23, 7:45 PM CST
Where: Davison County, 2.13 mi SSW of Mitchell
Measured: 61 kt (70 mph) estimated gust
Property damage: $10,000
Reported by: Trained Spotter
Coordinates: 43.690, -98.030

Thunderstorm winds blew the roof off a garage. The winds also caused tree damage, including large branches blown down.

Thunderstorm Wind, Davison

When: July 23, 7:45 PM CST
Where: Davison County, 5.73 mi NNW of Ethan
Measured: 61 kt (70 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.630, -98.010

Thunderstorm winds caused tree damage, including several branches blown down.

Thunderstorm Wind, Davison

When: July 23, 7:48 PM CST
Where: Davison County, 3.49 mi S of Mitchell
Measured: 61 kt (70 mph) estimated gust
Property damage: $10,000
Reported by: Trained Spotter
Coordinates: 43.670, -98.030

Thunderstorm winds caused damage to trees and power lines.

Thunderstorm Wind, Hanson

When: July 23, 7:55 PM CST
Where: Hanson County, Fulton
Measured: 61 kt (70 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.730, -97.820

Thunderstorm winds caused tree damage, including several trees blown down.

Thunderstorm Wind, Miner

When: July 23, 8:07 PM CST
Where: Miner County, 4.94 mi NNE of Howard Muni Arpt
Measured: 61 kt (70 mph) estimated gust
Property damage: $20,000
Reported by: Law Enforcement
Coordinates: 44.100, -97.510

Thunderstorm winds moved a house off its foundation.

Thunderstorm Wind, McCook

When: July 23, 8:10 PM CST
Where: McCook County, 4.86 mi S of Spencer
Measured: 61 kt (70 mph) estimated gust
Property damage: $10,000
Reported by: Trained Spotter
Coordinates: 43.660, -97.590

Thunderstorm winds blew over billboards and caused tree damage.

Thunderstorm Wind, McCook

When: July 23, 8:20 PM CST
Where: McCook County, 4.86 mi S of Salem
Measured: 55 kt (63 mph) measured gust
Reported by: Trained Spotter
Coordinates: 43.660, -97.390

Thunderstorm Wind, Lake

When: July 23, 8:27 PM CST
Where: Lake County, 0.5 mi E of Ramona
Measured: 52 kt (60 mph) estimated gust
Reported by: Emergency Manager
Coordinates: 44.120, -97.210

Thunderstorm winds caused tree damage, including several branches blown down.

Hail, Kingsbury

When: July 23, 8:30 PM CST
Where: Kingsbury County, 0.69 mi S of Arlington
Measured: 1 in hail
Reported by: COOP Observer
Coordinates: 44.360, -97.130

Thunderstorm Wind, Lake

When: July 23, 8:33 PM CST
Where: Lake County, 0.69 mi N of Junius
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 44.010, -97.250

Thunderstorm winds caused tree damage, including several branches blown down.

Hail, Bon Homme

When: July 23, 8:39 PM CST
Where: Bon Homme County, 0.51 mi W of Tyndall
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 42.980, -97.860

Thunderstorm Wind, Lake

When: July 23, 8:46 PM CST
Where: Lake County, 0.5 mi E of Wentworth
Measured: 56 kt (64 mph) estimated gust
Reported by: Emergency Manager
Coordinates: 44.000, -96.960

Thunderstorm winds caused tree damage, including a large tree blown down.

Thunderstorm Wind, Lincoln

When: July 23, 8:50 PM CST
Where: Lincoln County, 4.09 mi NW of Tea
Measured: 61 kt (70 mph) estimated gust
Property damage: $1.0 million
Reported by: Other Federal Agency
Coordinates: 43.490, -96.890

Thunderstorm winds destroyed 70 feet of scaffolding at a Lewis and Clark regional water project.

Thunderstorm Wind, Brookings

When: July 23, 8:55 PM CST to 9:00 PM CST
Where: Brookings County, 0.85 mi SW of Brookings
Measured: 52 kt (60 mph) estimated gust
Property damage: $20,000
Reported by: Trained Spotter
Coordinates: 44.310, -96.790

Thunderstorm winds blew down power lines and caused tree damage, including several trees blown down. The winds also partially peeled off the roof of a commercial storage building.

Thunderstorm Wind, Brookings

When: July 23, 8:55 PM CST
Where: Brookings County, 0.49 mi E of (Bkx)brookings Muni
Measured: 53 kt (61 mph) measured gust
Reported by: AWOS
Coordinates: 44.300, -96.810

Thunderstorm Wind, Moody

When: July 23, 9:03 PM CST
Where: Moody County, Egan
Measured: 61 kt (70 mph) estimated gust
Property damage: $10,000
Reported by: Emergency Manager
Coordinates: 44.000, -96.650

Thunderstorm winds blew the roofs off several storage bins.

Thunderstorm Wind, Moody

When: July 23, 9:04 PM CST
Where: Moody County, 0.99 mi W of Flandreau
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 44.050, -96.600

Thunderstorm winds caused tree damage, including several branches blown down.

Thunderstorm Wind, Turner

When: July 23, 9:10 PM CST
Where: Turner County, 3.27 mi NE of Irene
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.110, -97.120

Thunderstorm winds caused tree damage, including a large tree split, and several branches blown down.

Flash Flood, Brookings

When: July 23, 9:15 PM CST to 10:15 PM CST
Where: Brookings County, 1.64 mi WNW of Brookings to 1.64 mi SE of (Bkx)brookings Muni
Cause: Heavy Rain
Property damage: $25,000
Reported by: Trained Spotter
Coordinates: 44.330, -96.810

Heavy rain caused flash flooding of several streets and caused water damage to a few businesses.

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
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.
Funnel Cloud: A rotating column of cloud extending from a thunderstorm that did not reach the ground.
Tornado: A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

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

The same day elsewhere

Every storm in South Dakota in 2010 Every state in 2010 This day in weather history The tornado archive for South Dakota, 2010 Warnings in South Dakota, July 2010

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: 252000, 252001, 252002, 252003, 252004, 252005, 252006, 252007, 252008, 252009, 252010, 252011, 252012, 252013, 252014, 252015, 252016, 252017, 252018, 252019, 252020, 252021, 252022, 252023, 252024, 252025, 252472, 252473, 252474, 252475, 252476, 252477, 252478, 252479.