South Dakota, 2020

Hail and Damaging Wind in South Dakota, August 11, 2020

August 11, 2020 · NWS UNR · 2 events in 1 county or zone

A thunderstorm briefly became severe over central Butte County, producing hail and wind gusts to 60 mph west of Castle Rock.

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
2

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 thunderstorm briefly became severe over central Butte County, producing hail and wind gusts to 60 mph west of Castle Rock.

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 Aug 10, 9:26 PM MST, 4 hours 24 minutes earlier.

Area forecast discussion, Aug 10, 9:26 PM MST, 4 hours 24 minutes before
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Hazardous weather outlook, Aug 10, 8:57 AM MST, 16 hours 53 minutes before
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In the hours before

Special weather statement, Aug 11, 1:06 AM MST, 44 minutes before
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The radar

The Rapid City radar (KUDX), 107 km away, was scanning. The volume nearest the first event began at 08:51 UTC.

Open the radar archive at this moment

Event by event

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

Hail, Butte

When
August 11, 1:50 AM MST
Where
Butte County, 6 mi WSW of Castle Rock
Measured
0.88 in hail
Reported by
Public
Coordinates
44.937, -103.543

Thunderstorm Wind, Butte

When
August 11, 1:50 AM MST
Where
Butte County, 6 mi WSW of Castle Rock
Measured
52 kt (60 mph) estimated gust
Reported by
Public
Coordinates
44.937, -103.543

Winds were estimated at 60 mph.

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.

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

The same day elsewhere

More

Every storm in South Dakota in 2020Every state in 2020This day in weather historyWarnings in South Dakota, August 2020

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 2026-09-24. Each event’s entry at NCEI: 912433, 912434.