Hail in South Dakota, July 20, 2013

Name: Hail in South Dakota, July 20, 2013
Start: 2013-07-20T18:15
End: 2013-07-20T18:15
Location: South Dakota

July 20, 2013 · NWS UNR · 1 event in 1 county or zone

A left-moving supercell thunderstorm briefly developed over central Butte County and produced quarter size hail at 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

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

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 left-moving supercell thunderstorm briefly developed over central Butte County and produced quarter size hail at 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 Jul 20, 5:56 PM MST, 19 minutes earlier.

Area forecast discussion, Jul 20, 5:56 PM MST, 19 minutes before

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Hazardous weather outlook, Jul 20, 1:57 AM MST, 16 hours 18 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RAPID CITY SD
257 AM MDT SAT JUL 20 2013

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-211400-
BENNETT-BUTTE-CENTRAL BLACK HILLS-CUSTER CO PLAINS-FALL RIVER-HAAKON-
HARDING-HERMOSA FOOT HILLS-JACKSON-MELLETTE-NORTHEASTERN CROOK-
NORTHERN BLACK HILLS-NORTHERN CAMPBELL-NORTHERN FOOT HILLS-
NORTHERN MEADE CO PLAINS-PENNINGTON CO PLAINS-PERKINS-RAPID CITY-
SHANNON-SOUTHERN BLACK HILLS-SOUTHERN CAMPBELL-SOUTHERN FOOT HILLS-
SOUTHERN MEADE CO PLAINS-STURGIS/PIEDMONT FOOT HILLS-TODD-TRIPP-
WESTERN CROOK-WESTON-WYOMING BLACK HILLS-ZIEBACH-
257 AM MDT (357 AM CDT) SAT JUL 20 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN SOUTH DAKOTA AND
NORTHEASTERN WYOMING.

.DAY ONE...TODAY AND TONIGHT

ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY
INTO THIS EVENING. SEVERE THUNDERSTORMS...WITH LARGE HAIL AND
DAMAGING WIND GUSTS...ARE POSSIBLE OVER AND NEAR THE BLACK HILLS
AND OVER PARTS OF SOUTHWESTERN AND SOUTH CENTRAL SOUTH DAKOTA...
MAINLY THIS AFTERNOON AND EVENING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THERE IS A CHANCE OF THUNDERSTORMS AGAIN ON SUNDAY. THE BEST CHANCE
OF SEVERE THUNDERSTORMS ON SUNDAY WILL BE OVER SOUTHWESTERN
SOUTH DAKOTA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT.

&&

STAY TUNED TO NOAA WEATHER RADIO FOR FURTHER DETAILS OR UPDATES...
OR CHECK OUR WEB SITE AT WEATHER.GOV/RAPIDCITY

In the hours before

Local storm report, Jul 20, 5:08 PM MST, 1 hour 7 minutes before

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Local storm report, Jul 20, 5:20 PM MST, 55 minutes before

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Local storm report, Jul 20, 5:30 PM MST, 45 minutes before

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Local storm report, Jul 20, 5:32 PM MST, 43 minutes before

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Special weather statement, Jul 20, 5:45 PM MST, 30 minutes before

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Local storm report, Jul 20, 6:02 PM MST, 13 minutes before

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The radar

The Rapid City radar (KUDX), 105 km away, was scanning. The volume nearest the first event began at 01:12 UTC.

Open the radar archive at this moment

Event by event

1 hail. Local standard time, as filed.

Hail, Butte

When: July 20, 6:15 PM MST
Where: Butte County, Castle Rock
Measured: 1 in hail
Reported by: Public
Coordinates: 44.970, -103.430

What these are

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 2013 Every state in 2013 This day in weather history Warnings in South Dakota, July 2013

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: 466486.