Hail and Damaging Wind in South Dakota, July 29, 2011

Name: Hail and Damaging Wind in South Dakota, July 29, 2011
Start: 2011-07-29T17:13
End: 2011-07-29T18:08
Location: South Dakota

July 29, 2011 · NWS UNR · 3 events in 1 county or zone

A line of severe thunderstorms moved across Perkins County.

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: 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 line of severe thunderstorms moved across Perkins 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 29, 1:16 PM MST, 3 hours 57 minutes earlier.

Area forecast discussion, Jul 29, 1:16 PM MST, 3 hours 57 minutes before

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
216 PM MDT FRI JUL 29 2011

.DISCUSSION...CURRENT SURFACE MAP SHOWS TROF ACROSS EASTERN
WYOMING...WITH ABUNDANT TCU. DECENT INSTABILITY ACROSS THE AREA
WITH MLCAPE OF 1500-2500J/KG. CAP STILL HOLDING STRONG. WATER VAPOR
INDICATES WEAK SHORTWAVE MOVING INTO EASTERN WYOMING.
THUNDERSTORMS EXPECTED TO DEVELOP/STRENGTHEN OVER THE NEXT FEW
HOURS...WITH SUFFICIENT SHEAR FOR A FEW SUPERCELLS. THUNDERSTORMS
WILL DIMINISH LATER THIS EVENING.

ON SATURDAY...WEAK COLD FRONT SLIDES THROUGH WESTERN SOUTH DAKOTA.
EVEN THOUGH IT WILL BE UNSTABLE...WITH MLCAPE OF
2000-3000J/KG...STRONG CAP WILL BE IN PLACE. WITH LACK OF UPPER
LEVEL FORCING...ANY THUNDERSTORM DEVELOPMENT WILL BE ALONG COLD
FRONT. MORE THUNDERSTORMS POSSIBLE ON SUNDAY AS SHORTWAVE MOVES
THROUGH THE AREA DURING THE AFTERNOON/EVENING HOURS.

EXTENDED...UPPER RIDGE WILL REMAIN ANCHORED OVER THE SOUTHERN PLAINS
PUTTING NERN WY AND WRN SD IN A MOIST MONSOONAL SW FLOW ALOFT. THIS
WILL BRING A DAILY CHANCE OF THUNDERSTORMS TO THE REGION THRU THE
EXTENDED PERIOD. ABOVE AVERAGE TEMPS WILL CONTINUE INTO MONDAY
BEFORE A COLD FRONT USHERS IN SLIGHTLY COOLER AIR...BRINGING NEAR
AVERAGE TEMPS FOR THE REMAINDER OF THE WEEK.

&&

.AVIATION...SCT TSRA ARE EXPECTED MAINLY FROM THE BLKHLS EASTWARD
THIS AFTERNOON AND EVENING...BRINGING LCL IFR CIGS/VIS IN HEAVIER
PRECIP. SOME STORMS MAY BECOME SEVERE. OTHERWISE...VFR CONDITIONS
ARE EXPECTED.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

Hazardous weather outlook, Jul 29, 4:20 AM MST, 12 hours 53 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RAPID CITY SD
520 AM MDT FRI JUL 29 2011

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-301300-
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-
520 AM MDT (620 AM CDT) FRI JUL 29 2011

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

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS ARE FORECAST FOR WESTERN SOUTH DAKOTA TODAY
WITH ISOLATED STORMS IN NORTHEAST WYOMING.  THERE IS A SLIGHT RISK
OF SEVERE THUNDERSTORMS FROM THE BLACK HILLS INTO NORTHWEST SOUTH
DAKOTA...WITH LARGE HAIL AND DAMAGING WIND GUSTS POSSIBLE.

ADDITIONAL ISOLATED THUNDERSTORMS ARE POSSIBLE AFTER MIDNIGHT
AROUND THE BLACK HILLS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

AFTER A MOSTLY DRY DAY ON SATURDAY THERE IS A DAILY CHANCE OF
AFTERNOON AND EVENING THUNDERSTORMS FROM SUNDAY THROUGH THURSDAY. A
FEW STORMS MAY BE SEVERE PRODUCING LARGE HAIL AND DAMAGING WIND
GUSTS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER MAY BE NEEDED TODAY.

In the hours before

Local storm report, Jul 29, 4:50 PM MST, 23 minutes before

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Local storm report, Jul 29, 5:00 PM MST, 13 minutes before

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Local storm report, Jul 29, 5:02 PM MST, 11 minutes before

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Local storm report, Jul 29, 5:04 PM MST, 9 minutes before

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Local storm report, Jul 29, 5:11 PM MST, 2 minutes before

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Local storm report, Jul 29, 5:12 PM MST, 1 minute before

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The radar

The Rapid City radar (KUDX), 186 km away, was scanning. The volume nearest the first event began at 00:12 UTC.

Open the radar archive at this moment

Event by event

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

Hail, Perkins

When: July 29, 5:13 PM MST to 5:18 PM MST
Where: Perkins County, 13 mi W of Lodgepole
Measured: 0.88 in hail
Reported by: Trained Spotter
Coordinates: 45.800, -102.940

Thunderstorm Wind, Perkins

When: July 29, 5:13 PM MST to 5:18 PM MST
Where: Perkins County, 13 mi W of Lodgepole
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 45.800, -102.940

Wind gusts were estimated at 60 mph.

Hail, Perkins

When: July 29, 6:08 PM MST
Where: Perkins County, 7 mi SE of Meadow
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 45.458, -102.118

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

Every storm in South Dakota in 2011 Every state in 2011 This day in weather history Warnings in South Dakota, July 2011

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: 331175, 331176, 331177.