A severe thunderstorm developed rapidly on the west side of Rapid City and moved eastward through the downtown area and into Rapid Valley. A cluster of severe storms then formed east of Rapid City and moved east-southeast across west central South Dakota. The storm produced golf ball sized hail in Rapid City, with a gust of 68 mph at the National Weather Service office, which caused extensive vehicle damage. Large hail and strong wind gusts continued east across the plains.

Thunderstorm Wind in HAAKON, SOUTH DAKOTA
From 23-AUG-18 16:50:00 to 23-AUG-18 16:50:00 (MST-7)
Location: MIDLAND
Magnitude: 55.00 MG
Crop damage: 0.00K
Reported by: Mesonet

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:15:00 to 23-AUG-18 14:18:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.25 
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:19:00 to 23-AUG-18 14:19:00 (MST-7)
Location: RAPID CITY
Magnitude: 59.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:25:00 to 23-AUG-18 14:25:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.00 
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:20:00 to 23-AUG-18 14:20:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.75 
Crop damage: 0.00K
Reported by: Public

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:19:00 to 23-AUG-18 14:24:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.75 
Crop damage: 0.00K
Reported by: Official NWS Observations

The combination of large hail and strong wind gusts damaged vehicles.

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:25:00 to 23-AUG-18 14:25:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.50 
Crop damage: 0.00K
Reported by: Public

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:25:00 to 23-AUG-18 14:25:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.50 
Crop damage: 0.00K
Reported by: Public

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:26:00 to 23-AUG-18 14:26:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.00 
Crop damage: 0.00K
Reported by: Public

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:28:00 to 23-AUG-18 14:28:00 (MST-7)
Location: (RAP)RAPID CITY ARPT
Magnitude: 1.75 
Crop damage: 0.00K
Reported by: NWS Employee

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:29:00 to 23-AUG-18 14:29:00 (MST-7)
Location: (RAP)RAPID CITY ARPT
Magnitude: 1.25 
Crop damage: 0.00K
Reported by: NWS Employee

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 14:35:00 to 23-AUG-18 14:35:00 (MST-7)
Location: RAPID CITY
Magnitude: 1.50 
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 15:35:00 to 23-AUG-18 15:35:00 (MST-7)
Location: WALL
Magnitude: 63.00 MG
Crop damage: 0.00K
Reported by: RAWS

Hail in JACKSON, SOUTH DAKOTA
From 23-AUG-18 15:48:00 to 23-AUG-18 15:48:00 (MST-7)
Location: INTERIOR
Magnitude: 1.00 
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 15:39:00 to 23-AUG-18 15:39:00 (MST-7)
Location: WALL
Magnitude: 1.00 
Crop damage: 0.00K
Reported by: Storm Chaser

Hail in PENNINGTON, SOUTH DAKOTA
From 23-AUG-18 15:50:00 to 23-AUG-18 15:50:00 (MST-7)
Location: QUINN
Magnitude: 1.50 
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in JACKSON, SOUTH DAKOTA
From 23-AUG-18 16:01:00 to 23-AUG-18 16:01:00 (MST-7)
Location: INTERIOR
Magnitude: 52.00 EG
Crop damage: 0.00K
Reported by: Trained Spotter

Wind gusts were estimated at 60 mph.

Thunderstorm Wind in JACKSON, SOUTH DAKOTA
From 23-AUG-18 16:10:00 to 23-AUG-18 16:10:00 (MST-7)
Location: CACTUS FLATS
Magnitude: 66.00 MG
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in JACKSON, SOUTH DAKOTA
From 23-AUG-18 16:55:00 to 23-AUG-18 16:55:00 (MST-7)
Location: BELVIDERE
Magnitude: 66.00 MG
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in CUSTER, SOUTH DAKOTA
From 23-AUG-18 15:04:00 to 23-AUG-18 15:04:00 (MST-7)
Location: FOLSOM
Magnitude: 52.00 EG
Crop damage: 0.00K
Reported by: Public

Wind gusts were estimated at 60 mph.

Hail in CUSTER, SOUTH DAKOTA
From 23-AUG-18 15:00:00 to 23-AUG-18 15:00:00 (MST-7)
Location: FOLSOM
Magnitude: 1.75 
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in HAAKON, SOUTH DAKOTA
From 23-AUG-18 16:26:00 to 23-AUG-18 16:26:00 (MST-7)
Location: (PHP)PHILIP ARPT
Magnitude: 53.00 MG
Crop damage: 0.00K
Reported by: ASOS