A severe thunderstorm moved northeastward from Wyoming across the Black Hills. The storm initially produced very large hail over the central Black Hills and then strong wind gusts as it began to weaken over the Rapid City area. Minor urban flooding occurred over a section of east Rapid City.

Hail in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:00:00 to 27-JUL-15 16:00:00 (MST-7)
Location: HILL CITY
Magnitude: 3.50 
Crop damage: 0.00K
Reported by: NWS Employee

Hail in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:00:00 to 27-JUL-15 16:15:00 (MST-7)
Location: MT RUSHMORE
Magnitude: 1.75 
Crop damage: 0.00K
Reported by: SHAVE Project

Hail in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:45:00 to 27-JUL-15 16:45:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.25 
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:48:00 to 27-JUL-15 16:48:00 (MST-7)
Location: RAPID CITY
Magnitude: 60.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Hail in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:15:00 to 27-JUL-15 16:15:00 (MST-7)
Location: KEYSTONE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CUSTER, SOUTH DAKOTA
From 27-JUL-15 16:15:00 to 27-JUL-15 16:15:00 (MST-7)
Location: CUSTER
Magnitude: 1.50 
Crop damage: 0.00K
Reported by: Park/Forest Service

Ping pong ball sized hail was reported at Sylvan Lake.

Hail in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:15:00 to 27-JUL-15 16:15:00 (MST-7)
Location: KEYSTONE
Magnitude: 1.50 
Crop damage: 0.00K
Reported by: SHAVE Project

Hail in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:23:00 to 27-JUL-15 16:23:00 (MST-7)
Location: ROCKERVILLE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm Wind in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:42:00 to 27-JUL-15 16:42:00 (MST-7)
Location: RAPID CITY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Wind gusts were estimated at 60 mph.

Thunderstorm Wind in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:55:00 to 27-JUL-15 17:05:00 (MST-7)
Location: (RAP)RAPID CITY ARPT
Magnitude: 63.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 15:35:00 to 27-JUL-15 15:35:00 (MST-7)
Location: HILL CITY
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Thunderstorm Wind in MEADE, SOUTH DAKOTA
From 27-JUL-15 16:58:00 to 27-JUL-15 16:58:00 (MST-7)
Location: ELLSWORTH AFB
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Wind gusts were estimated at 60 mph.

Flood in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 18:00:00 to 27-JUL-15 20:00:00 (MST-7)
Location: RAPID CITY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Runoff from heavy rainfall covered streets and parking lots between Elk Vale Road and Concourse Drive.

Thunderstorm Wind in PENNINGTON, SOUTH DAKOTA
From 27-JUL-15 16:27:00 to 27-JUL-15 16:27:00 (MST-7)
Location: HAYWARD
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Wind gusts were estimated at 60 mph.