Flash Flood and Hail in South Dakota, July 19 to 21, 2019

Name: Flash Flood and Hail in South Dakota, July 19 to 21, 2019
Start: 2019-07-19T22:55
End: 2019-07-21T06:30
Location: South Dakota

July 19 to 21, 2019 · NWS UNR · 3 events in 2 counties and zones

A severe thunderstorm tracked eastward from northeastern Wyoming across southern Butte and northwestern Meade Counties. The storm produced hail and strong wind gusts.

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

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The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 3

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 UNR wrote it up.

A severe thunderstorm tracked eastward from northeastern Wyoming across southern Butte and northwestern Meade Counties. The storm produced hail and strong wind gusts. Runoff from heavy rainfall overnight on already saturated ground caused flooding across parts of northeastern Butte County.

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 Rapid City, SD wrote its last area forecast discussion before the first event at Jul 19, 10:10 PM MST, 45 minutes earlier.

Area forecast discussion, Jul 19, 10:10 PM MST, 45 minutes before

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In the hours before

Special weather statement, Jul 19, 8:43 PM MST, 2 hours 12 minutes before

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Special weather statement, Jul 19, 9:21 PM MST, 1 hour 34 minutes before

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Special weather statement, Jul 19, 10:37 PM MST, 18 minutes before

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The radar

The Rapid City radar (KUDX), 101 km away, was scanning. The volume nearest the first event began at 05:54 UTC.

Open the radar archive at this moment

Event by event

1 hail, 1 thunderstorm wind, 1 flash flood. Local standard time, as filed.

Hail, Butte

When: July 19, 10:55 PM MST
Where: Butte County, 4 mi NNW of Belle Fourche Reservoir
Measured: 1 in hail
Reported by: Public
Coordinates: 44.783, -103.711

Thunderstorm Wind, Meade

When: July 20, 12:05 AM MST
Where: Meade County, 7.62 mi N of Stoneville
Measured: 52 kt (60 mph) estimated gust
Reported by: Public
Coordinates: 44.840, -102.660

Wind gusts were estimated at 60 mph.

Flash Flood, Butte

When: July 21, 4:00 AM MST to 6:30 AM MST
Where: Butte County, 10.02 mi WNW of Hoover to 15.26 mi N of Castle Rock
Cause: Heavy Rain
Reported by: COOP Observer
Coordinates: 45.180, -103.450

Runoff from heavy rain overnight caused flash flooding along the South Fork of the Moreau River near Hoover.

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.
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 2019 Every state in 2019 This day in weather history Warnings in South Dakota, July 2019

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: 842132, 842133, 855543.