A strong short-wave trough moved into the Northern Plains as a slow moving warm front lifted through North Dakota. Very strong instability developed by afternoon, along with increased deep layer shear. The initial storms occurred over west-central and northwest North Dakota. The main concern with these storms was large hail and tornadoes. Multiple tornadoes occurred over western McKenzie County over a similar location, and one occurred in Williams County. Photos of the tornadoes submitted to the National Weather Service indicate that one of them in McKenzie County was quite large. With that said, no damage was reported given the tornadoes occurred in rugged terrain over a rural area, so all were rated EF-U, EF Unknown. As the evening went on, the threats shifted to a mix of strong winds, hail, and heavy rain. The city of Williston was hit the hardest with multiple storms passing over in a short period of time. Flash flooding occurred in the city, which floated vehicles and flooded basements. Hail to the size of tennis balls also fell, causing extensive home and vehicle damage. In addition, very strong winds were reported at the Williston airport, with gusts to 82 mph with one storm, then gusts to 93 mph with the next, causing roof damage. Later in the night the storms became more linear and grew towards the south, while the overall lines moved east. Wind became the primary concern as the storms moved towards the James River Valley where multiple wind damage events occurred. For the whole event, the largest hail reported was the size of tennis balls, in Williston in Williams County. The strongest reported wind gust was 93 mph at the Williston Airport, also in Williams County.

Hail in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 16:30:00 to 10-JUN-21 16:33:00 (MST-7)
Location: EAST FAIRVIEW
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 18:45:00 to 10-JUN-21 18:49:00 (MST-7)
Location: FAIRVIEW
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Hail in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 20:36:00 to 10-JUN-21 20:40:00 (CST-6)
Location: WILLISTON
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 21:36:00 to 10-JUN-21 21:40:00 (CST-6)
Location: BUFORD
Magnitude: 65.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Public

A large pole barn was heavily damaged with one end of the building and an adjacent part of the roof destroyed.

Thunderstorm Wind in STARK, NORTH DAKOTA
From 10-JUN-21 21:51:00 to 10-JUN-21 21:54:00 (MST-7)
Location: TAYLOR
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The public estimated wind gusts to 60 mph.

Hail in STARK, NORTH DAKOTA
From 10-JUN-21 21:52:00 to 10-JUN-21 21:54:00 (MST-7)
Location: RICHARDTON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in STARK, NORTH DAKOTA
From 10-JUN-21 21:54:00 to 10-JUN-21 21:57:00 (MST-7)
Location: RICHARDTON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in STARK, NORTH DAKOTA
From 10-JUN-21 21:58:00 to 10-JUN-21 22:01:00 (MST-7)
Location: RICHARDTON
Magnitude: 56.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Public

Trees were damaged.

Thunderstorm Wind in STARK, NORTH DAKOTA
From 10-JUN-21 22:10:00 to 10-JUN-21 22:13:00 (MST-7)
Location: TAYLOR
Magnitude: 56.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

One inch diameter tree limbs were broken. Some shingles blew off a structure.

Hail in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 17:23:00 to 10-JUN-21 17:26:00 (MST-7)
Location: ALEXANDER
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 19:00:00 to 10-JUN-21 19:04:00 (CST-6)
Location: RAY
Magnitude: 57.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 20:41:00 to 10-JUN-21 20:45:00 (CST-6)
Location: TRENTON
Magnitude: 65.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

A roof was damaged.

Thunderstorm Wind in STARK, NORTH DAKOTA
From 10-JUN-21 22:01:00 to 10-JUN-21 22:03:00 (MST-7)
Location: RICHARDTON
Magnitude: 65.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 22:20:00 to 10-JUN-21 22:23:00 (CST-6)
Location: ALAMO
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 22:39:00 to 10-JUN-21 22:42:00 (CST-6)
Location: HANKS
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in MORTON, NORTH DAKOTA
From 10-JUN-21 23:15:00 to 10-JUN-21 23:21:00 (CST-6)
Location: GLEN ULLIN
Magnitude: 65.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Public

Damage occurred in and around the city of Glen Ullin. About a mile west of town, outbuildings were severely damaged, and a roof on an industrial building was damaged. In town, A five inch diameter tree was broken over.

Thunderstorm Wind in MERCER, NORTH DAKOTA
From 10-JUN-21 23:38:00 to 10-JUN-21 23:40:00 (CST-6)
Location: GOLDEN VLY
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Hail in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 18:01:00 to 10-JUN-21 18:05:00 (MST-7)
Location: EAST FAIRVIEW
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 19:40:00 to 10-JUN-21 19:42:00 (CST-6)
Location: TIOGA
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Hail in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 20:36:00 to 10-JUN-21 20:54:00 (CST-6)
Location: WILLISTON
Magnitude: 2.50 
Property damage: 1.00M
Crop damage: 0.00K
Reported by: COOP Observer

This was the first of multiple rounds of hail to strike the Williston area the evening of June 10. With this round, hail up to the size of tennis balls fell over the Williston area. This caused damage to many roofs and vehicles, including damaging every police car in the city, and every vehicle parked in the Williams County facility lot. In addition, strong winds with this storm blew a roof off a truck and car wash.

Hail in BURKE, NORTH DAKOTA
From 10-JUN-21 22:46:00 to 10-JUN-21 22:49:00 (CST-6)
Location: BATTLEVIEW
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in MORTON, NORTH DAKOTA
From 10-JUN-21 23:15:00 to 10-JUN-21 23:18:00 (CST-6)
Location: HEBRON
Magnitude: 56.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

Tree damage occurred.

Thunderstorm Wind in MOUNTRAIL, NORTH DAKOTA
From 10-JUN-21 23:43:00 to 10-JUN-21 23:46:00 (CST-6)
Location: STANLEY
Magnitude: 65.00 EG
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Six inch diameter branches from a one-hundred year old tree were broken down.

Thunderstorm Wind in MERCER, NORTH DAKOTA
From 10-JUN-21 23:47:00 to 10-JUN-21 23:50:00 (CST-6)
Location: BEULAH
Magnitude: 61.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in BURLEIGH, NORTH DAKOTA
From 11-JUN-21 01:02:00 to 11-JUN-21 01:05:00 (CST-6)
Location: MOFFIT
Magnitude: 69.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in KIDDER, NORTH DAKOTA
From 11-JUN-21 01:17:00 to 11-JUN-21 01:20:00 (CST-6)
Location: STEELE MUNI ARPT
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Hail in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 18:10:00 to 10-JUN-21 18:13:00 (MST-7)
Location: EAST FAIRVIEW
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 19:42:00 to 10-JUN-21 19:45:00 (MST-7)
Location: ALEXANDER
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in DIVIDE, NORTH DAKOTA
From 10-JUN-21 20:55:00 to 10-JUN-21 20:58:00 (CST-6)
Location: ALKABO
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in WARD, NORTH DAKOTA
From 11-JUN-21 01:08:00 to 11-JUN-21 01:12:00 (CST-6)
Location: (MIB)MINOT AFB
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Thunderstorm Wind in KIDDER, NORTH DAKOTA
From 11-JUN-21 01:37:00 to 11-JUN-21 01:41:00 (CST-6)
Location: STEELE
Magnitude: 65.00 EG
Property damage: 40.00K
Crop damage: 0.00K
Reported by: Public

A pole barn building was blown down.

Thunderstorm Wind in STUTSMAN, NORTH DAKOTA
From 11-JUN-21 02:33:00 to 11-JUN-21 02:36:00 (CST-6)
Location: (JMS)JAMESTOWN MUNI
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in LA MOURE, NORTH DAKOTA
From 11-JUN-21 02:51:00 to 11-JUN-21 02:58:00 (CST-6)
Location: LA MOURE
Magnitude: 65.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A camper was blown onto its side, and a pontoon boat on a lift was rolled over, with the dock damaged.

Thunderstorm Wind in DICKEY, NORTH DAKOTA
From 11-JUN-21 03:00:00 to 11-JUN-21 03:05:00 (CST-6)
Location: OAKES
Magnitude: 70.00 EG
Property damage: 200.00K
Crop damage: 0.00K
Reported by: Public

Several large tree branches around Oakes were snapped. Garaged doors were blown in, and a home TV tower was bent over.

Hail in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 20:10:00 to 10-JUN-21 20:13:00 (CST-6)
Location: (ISN)SLOULIN FLD WIL
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm Wind in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 21:15:00 to 10-JUN-21 21:18:00 (MST-7)
Location: CHARBONNEAU
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in LA MOURE, NORTH DAKOTA
From 11-JUN-21 03:10:00 to 11-JUN-21 03:14:00 (CST-6)
Location: VERONA
Magnitude: 61.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

A 40 foot tall evergreen was uprooted and fell onto a shed.

Tornado in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 16:32:00 to 10-JUN-21 16:38:00 (MST-7)
Location: EAST FAIRVIEW
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The tornado touched down in an open field southwest of Sather Dam. There was no damage to evaluate and so by National Weather Service policy the tornado is rated EF Unknown.

Hail in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 21:32:00 to 10-JUN-21 21:35:00 (CST-6)
Location: RAY
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Thunderstorm Wind in STARK, NORTH DAKOTA
From 10-JUN-21 21:55:00 to 10-JUN-21 21:57:00 (MST-7)
Location: RICHARDTON
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 18:34:00 to 10-JUN-21 18:37:00 (CST-6)
Location: (ISN)SLOULIN FLD WIL
Magnitude: 57.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 21:56:00 to 10-JUN-21 21:58:00 (CST-6)
Location: (ISN)SLOULIN FLD WIL
Magnitude: 71.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 22:20:00 to 10-JUN-21 22:23:00 (CST-6)
Location: HANKS
Magnitude: 70.00 EG
Property damage: 150.00K
Crop damage: 0.00K
Reported by: Utility Company

Mountrail-Williams electric recorded 52 poles broken, which includes a one-mile long stretch where every pole was broken southeast of Grenora. In addition, a large tree was blown down in Zahl.

Thunderstorm Wind in MCLEAN, NORTH DAKOTA
From 11-JUN-21 00:06:00 to 11-JUN-21 00:09:00 (CST-6)
Location: EMMET
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in MCINTOSH, NORTH DAKOTA
From 11-JUN-21 01:50:00 to 11-JUN-21 01:54:00 (CST-6)
Location: ASHLEY
Magnitude: 65.00 EG
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Public

Large trees were blown down.

Thunderstorm Wind in STUTSMAN, NORTH DAKOTA
From 11-JUN-21 02:44:00 to 11-JUN-21 02:48:00 (CST-6)
Location: KENSAL
Magnitude: 61.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Public

A street light was bent at the base.

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 20:28:00 to 10-JUN-21 20:32:00 (CST-6)
Location: TRENTON
Magnitude: 70.00 EG
Property damage: 40.00K
Crop damage: 0.00K
Reported by: Public

Part of a roof was blown off a building, and another small building was blown over.

Hail in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 22:27:00 to 10-JUN-21 22:30:00 (CST-6)
Location: WILLISTON
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm Wind in MERCER, NORTH DAKOTA
From 10-JUN-21 23:30:00 to 10-JUN-21 23:35:00 (CST-6)
Location: GOLDEN VLY
Magnitude: 70.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Public

A recreational vehicle was tipped over, and a small garage was shifted off its foundation.

Thunderstorm Wind in FOSTER, NORTH DAKOTA
From 11-JUN-21 02:53:00 to 11-JUN-21 02:55:00 (CST-6)
Location: GLENFIELD
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Tornado in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 16:12:00 to 10-JUN-21 16:15:00 (MST-7)
Location: FAIRVIEW
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The tornado touched down in an open field northeast of Skaar. There was no damage to evaluate and so by National Weather Service policy the tornado is rated EF Unknown.

Tornado in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 20:57:00 to 10-JUN-21 21:00:00 (CST-6)
Location: WILLISTON
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Storm Chaser

The tornado touched down in an open field east of Williston. There was no damage to evaluate and so by National Weather Service policy the tornado is rated EF Unknown.

Thunderstorm Wind in STARK, NORTH DAKOTA
From 10-JUN-21 21:57:00 to 10-JUN-21 21:59:00 (MST-7)
Location: ANTELOPE
Magnitude: 61.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

Three inch tree limbs were broken, and some power poles were broken.

Hail in MORTON, NORTH DAKOTA
From 10-JUN-21 23:31:00 to 10-JUN-21 23:34:00 (CST-6)
Location: GLEN ULLIN
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 22:09:00 to 10-JUN-21 22:27:00 (CST-6)
Location: WILLISTON
Magnitude: 1.50 
Property damage: 200.00K
Crop damage: 0.00K
Reported by: COOP Observer

This is the second in a series of storms to strike the Williston area.  Ping pong size hail accompanied this storm, along with very heavy rainfall. Additional damage was done to roofs and vehicles.

Flash Flood in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 21:00:00 to 11-JUN-21 00:00:00 (CST-6)
Location: (ISN)SLOULIN FLD WIL
Flood cause: Heavy Rain
Property damage: 800.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Up to five inches of rain fell in the Williston area as multiple rounds of thunderstorms passed through. This led to widespread street flooding, with water affecting many homes. In addition, multiple vehicles were damaged by the flood waters. This includes a combination of parked vehicles and ones where the driver entered the flood waters.

Hail in WARD, NORTH DAKOTA
From 10-JUN-21 21:58:00 to 10-JUN-21 22:02:00 (CST-6)
Location: KENMARE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in STARK, NORTH DAKOTA
From 10-JUN-21 22:05:00 to 10-JUN-21 22:14:00 (MST-7)
Location: RICHARDTON
Magnitude: 64.00 MG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Storm Chaser

A tree was down in town, along with a power line.

Thunderstorm Wind in WILLIAMS, NORTH DAKOTA
From 10-JUN-21 22:34:00 to 10-JUN-21 22:37:00 (CST-6)
Location: (ISN)SLOULIN FLD WIL
Magnitude: 81.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in WARD, NORTH DAKOTA
From 11-JUN-21 00:17:00 to 11-JUN-21 00:21:00 (CST-6)
Location: RYDER
Magnitude: 61.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Public

A hopper-style grain bin blew over.

Thunderstorm Wind in MORTON, NORTH DAKOTA
From 10-JUN-21 23:14:00 to 10-JUN-21 23:17:00 (CST-6)
Location: HEBRON
Magnitude: 61.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

Three inch diameter tree limbs were broken, and some power poles were broken.

Thunderstorm Wind in MORTON, NORTH DAKOTA
From 10-JUN-21 23:38:00 to 10-JUN-21 23:41:00 (CST-6)
Location: NEW SALEM
Magnitude: 57.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Thunderstorm Wind in BOTTINEAU, NORTH DAKOTA
From 11-JUN-21 01:56:00 to 11-JUN-21 02:00:00 (CST-6)
Location: WILLOW CITY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter estimated thunderstorm wind gusts of 60 mph.

Thunderstorm Wind in LA MOURE, NORTH DAKOTA
From 11-JUN-21 03:00:00 to 11-JUN-21 03:04:00 (CST-6)
Location: LA MOURE
Magnitude: 65.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Public

Tree branches several inches wide punctured a house roof.

Thunderstorm Wind in MERCER, NORTH DAKOTA
From 10-JUN-21 23:43:00 to 10-JUN-21 23:46:00 (CST-6)
Location: BEULAH
Magnitude: 61.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

A chicken coop was destroyed.

Tornado in MCKENZIE, NORTH DAKOTA
From 10-JUN-21 17:55:00 to 10-JUN-21 18:13:00 (MST-7)
Location: FAIRVIEW
Tornado F-scale: EFU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The tornado touched down and moved through open rangeland in rugged terrain southwest of Sather Dam, near the location of the previous tornado report. This tornado was noted to be quite large, and long lasting. There was no damage to evaluate and so by National Weather Service policy the tornado is rated EF Unknown.