A frontal boundary moved into western North Dakota with a very moist air-mass noted ahead of it. A broad area of convection developed by late afternoon, and moved east into the evening. Very strong instability was noted, along with increasing deep layer shear, which led to the development of severe thunderstorms. Very strong wind gusts became the primary threat, though some large hail events also occurred. The strongest series of storms occurred over McLean County. Golf ball sized hail fell near Garrison in the late afternoon. In the early evening, 95 mph wind gusts occurred around  Underwood. This led to substantial damage to trees throughout the city, along with damage to vehicles and roofs.

Hail in MCLEAN, NORTH DAKOTA
From 23-JUL-15 16:15:00 to 23-JUL-15 16:20:00 (CST-6)
Location: EMMET
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in WARD, NORTH DAKOTA
From 23-JUL-15 16:21:00 to 23-JUL-15 16:24:00 (CST-6)
Location: DOUGLAS
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm wind gust speed was estimated off of a video replay.

Thunderstorm Wind in MORTON, NORTH DAKOTA
From 23-JUL-15 16:35:00 to 23-JUL-15 16:38:00 (CST-6)
Location: GLEN ULLIN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm wind gust speed was estimated by a trained spotter.

Hail in MCLEAN, NORTH DAKOTA
From 23-JUL-15 17:02:00 to 23-JUL-15 17:05:00 (CST-6)
Location: GARRISON MUNI ARPT
Magnitude: 1.75 
Property damage: 150.00K
Crop damage: 150.00K
Reported by: Trained Spotter

Thunderstorm Wind in GRANT, NORTH DAKOTA
From 23-JUL-15 17:20:00 to 23-JUL-15 17:23:00 (MST-7)
Location: HEIL
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The thunderstorm wind gust speed was estimated by the public.

Thunderstorm Wind in MCLEAN, NORTH DAKOTA
From 23-JUL-15 17:35:00 to 23-JUL-15 17:38:00 (CST-6)
Location: RIVERDALE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The strong thunderstorm wind gusts were estimated by a trained spotter.

Thunderstorm Wind in MCLEAN, NORTH DAKOTA
From 23-JUL-15 17:48:00 to 23-JUL-15 17:51:00 (CST-6)
Location: UNDERWOOD
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in ROLETTE, NORTH DAKOTA
From 23-JUL-15 18:35:00 to 23-JUL-15 18:37:00 (CST-6)
Location: MYLO
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Thunderstorm Wind in MCLEAN, NORTH DAKOTA
From 23-JUL-15 18:40:00 to 23-JUL-15 18:43:00 (CST-6)
Location: WILTON
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in BURLEIGH, NORTH DAKOTA
From 23-JUL-15 19:00:00 to 23-JUL-15 19:03:00 (CST-6)
Location: REGAN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm wind gust speed was estimated by a trained spotter.

Hail in MORTON, NORTH DAKOTA
From 23-JUL-15 19:09:00 to 23-JUL-15 19:11:00 (CST-6)
Location: MANDAN
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Hail in KIDDER, NORTH DAKOTA
From 23-JUL-15 19:50:00 to 23-JUL-15 19:53:00 (CST-6)
Location: TUTTLE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in FOSTER, NORTH DAKOTA
From 23-JUL-15 20:56:00 to 23-JUL-15 20:59:00 (CST-6)
Location: CARRINGTON
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm wind gust speed was measured by a law enforcement official.

Hail in OLIVER, NORTH DAKOTA
From 23-JUL-15 18:26:00 to 23-JUL-15 18:29:00 (CST-6)
Location: CENTER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in STUTSMAN, NORTH DAKOTA
From 23-JUL-15 22:00:00 to 23-JUL-15 22:03:00 (CST-6)
Location: JAMESTOWN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm wind gust speed was estimated by a trained spotter.

Thunderstorm Wind in OLIVER, NORTH DAKOTA
From 23-JUL-15 18:32:00 to 23-JUL-15 18:38:00 (CST-6)
Location: CENTER
Magnitude: 65.00 EG
Property damage: 20.00K
Crop damage: 30.00K
Reported by: Public

A farm was impacted by the severe thunderstorm winds. Fences were blown down, garage doors were blown out, roofs were damaged, and farmyard items were blown over and rolled. Crop damage was also reported.

Thunderstorm Wind in MCLEAN, NORTH DAKOTA
From 23-JUL-15 17:44:00 to 23-JUL-15 17:49:00 (CST-6)
Location: UNDERWOOD
Magnitude: 83.00 EG
Property damage: 500.00K
Crop damage: 200.00K
Reported by: Emergency Manager

Thunderstorm wind gust speed was based on damage photos. Multiple roofs were damaged. Large trees were snapped and uprooted, and one tree landed on a car and crushed it. Various other vehicles were damaged by falling trees and limbs. A camper was overturned.