Considerable forcing and ascent and deep-layer wind fields resulted in widespread and intense thunderstorm activity. Boundary layer dewpoints in the 50s, steep lapse rates and pronounced veering of winds with height fostered an environment favorable for supercells capable of large hail and tornadoes.

Thunderstorm Wind in YELLOWSTONE, MONTANA
From 06-JUN-11 20:54:00 to 06-JUN-11 20:54:00 (MST-7)
Location: NIBES
Magnitude: 61.00 EG
Reported by: Trained Spotter

A storage shed was blown apart and flew 60-70 feet into a center pivot.

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:01:00 to 06-JUN-11 18:01:00 (MST-7)
Location: BIG TIMBER ARPT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:07:00 to 06-JUN-11 18:07:00 (MST-7)
Location: BIG TIMBER ARPT
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:45:00 to 06-JUN-11 18:45:00 (MST-7)
Location: COLUMBUS
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 19:05:00 to 06-JUN-11 19:05:00 (MST-7)
Location: WHEAT BASIN
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 19:03:00 to 06-JUN-11 19:03:00 (MST-7)
Location: COLUMBUS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:48:00 to 06-JUN-11 18:48:00 (MST-7)
Location: COLUMBUS
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:10:00 to 06-JUN-11 18:10:00 (MST-7)
Location: BIG TIMBER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:15:00 to 06-JUN-11 18:15:00 (MST-7)
Location: GREYCLIFF
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:28:00 to 06-JUN-11 18:28:00 (MST-7)
Location: COLUMBUS
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:30:00 to 06-JUN-11 18:30:00 (MST-7)
Location: COLUMBUS
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

There was heavy damage to a car windshield.

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:30:00 to 06-JUN-11 18:30:00 (MST-7)
Location: GREYCLIFF
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:40:00 to 06-JUN-11 18:40:00 (MST-7)
Location: COLUMBUS
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Funnel Cloud in STILLWATER, MONTANA
From 06-JUN-11 19:13:00 to 06-JUN-11 19:13:00 (MST-7)
Location: MOLT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 19:15:00 to 06-JUN-11 19:15:00 (MST-7)
Location: RAPELJE
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:40:00 to 06-JUN-11 18:40:00 (MST-7)
Location: COLUMBUS
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in GOLDEN VALLEY, MONTANA
From 06-JUN-11 19:04:00 to 06-JUN-11 19:04:00 (MST-7)
Location: RYEGATE ARPT
Magnitude: 1.50 
Crop damage: 0.00K
Reported by: Public

A rancher reported the loss of 180 head of cattle as a result of running off a 200ft cliff to escape the hail.

Hail in MUSSELSHELL, MONTANA
From 06-JUN-11 20:20:00 to 06-JUN-11 20:20:00 (MST-7)
Location: ELSO
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Funnel Cloud in MUSSELSHELL, MONTANA
From 06-JUN-11 20:25:00 to 06-JUN-11 20:25:00 (MST-7)
Location: ELSO
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail in MUSSELSHELL, MONTANA
From 06-JUN-11 20:30:00 to 06-JUN-11 20:30:00 (MST-7)
Location: ROUNDUP
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:15:00 to 06-JUN-11 18:15:00 (MST-7)
Location: BIG TIMBER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:18:00 to 06-JUN-11 18:18:00 (MST-7)
Location: COLUMBUS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:18:00 to 06-JUN-11 18:18:00 (MST-7)
Location: BIG TIMBER
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Funnel Cloud in SWEET GRASS, MONTANA
From 06-JUN-11 18:20:00 to 06-JUN-11 18:20:00 (MST-7)
Location: GREYCLIFF
Property damage: 0.00K
Crop damage: 0.00K
Reported by: County Official

A funnel cloud was spotted between Greycliff and Big Timber.

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:20:00 to 06-JUN-11 18:20:00 (MST-7)
Location: NYE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:25:00 to 06-JUN-11 18:25:00 (MST-7)
Location: BIG TIMBER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:25:00 to 06-JUN-11 18:25:00 (MST-7)
Location: COLUMBUS
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 06-JUN-11 18:25:00 to 06-JUN-11 18:25:00 (MST-7)
Location: COLUMBUS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Funnel Cloud in YELLOWSTONE, MONTANA
From 06-JUN-11 20:37:00 to 06-JUN-11 20:37:00 (MST-7)
Location: BILLINGS HGTS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MUSSELSHELL, MONTANA
From 06-JUN-11 21:00:00 to 06-JUN-11 21:00:00 (MST-7)
Location: GAGE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Funnel Cloud in YELLOWSTONE, MONTANA
From 06-JUN-11 21:08:00 to 06-JUN-11 21:08:00 (MST-7)
Location: POMPEYS PILLAR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotters reported several funnel clouds 2 miles north of Pompeys Pillar.

Hail in ROSEBUD, MONTANA
From 06-JUN-11 21:45:00 to 06-JUN-11 21:45:00 (MST-7)
Location: SUMATRA
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in YELLOWSTONE, MONTANA
From 06-JUN-11 21:46:00 to 06-JUN-11 21:46:00 (MST-7)
Location: NEWTON GROVE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tornado in YELLOWSTONE, MONTANA
From 06-JUN-11 20:30:00 to 06-JUN-11 20:35:00 (MST-7)
Location: SHEPHERD
Tornado F-scale: EF0
Reported by: NWS Storm Survey

At approximately 930pm, a tornado briefly touched down at a residence 5 miles west of Shepherd. The path of damage was about 50 yards wide and extended to the northeast for about 200 yards. A roof was torn off of a garage and a shed. Debris that was blown into a nearby house caused additional damage to windows and siding. Three power poles in the area sustained damage. In addition, a horse trailer was flipped on its side.

Flash Flood in STILLWATER, MONTANA
From 06-JUN-11 19:42:00 to 06-JUN-11 21:42:00 (MST-7)
Location: COLUMBUS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A thunderstorm producing 0.63 inches of rain in 20 minutes resulted in water over some roads just northwest of Columbus.

Flash Flood in GOLDEN VALLEY, MONTANA
From 06-JUN-11 20:12:00 to 06-JUN-11 22:12:00 (MST-7)
Location: RYEGATE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A thunderstorm producing between 5.00 and 5.5 inches of rain resulted in flash flooding and flooded homes in Ryegate.

Tornado in YELLOWSTONE, MONTANA
From 06-JUN-11 19:42:00 to 06-JUN-11 19:45:00 (MST-7)
Location: RIMROCK
Tornado F-scale: EF0
Reported by: NWS Storm Survey

At approximately 845pm, a tornado briefly touched down at a residence 5 miles east of Molt. A 15 foot grain bin was destroyed, picked up and thrown into an outbuilding 50 feet to the southwest. Additional minor damage occurred to the siding and room on a nearby house.

Hail in SWEET GRASS, MONTANA
From 06-JUN-11 18:02:00 to 06-JUN-11 18:02:00 (MST-7)
Location: MELVILLE
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter