Atmospheric conditions during the evening of the 3rd into the early morning hours on the 4th were favorable for organized storms, including supercells and small bowing segments which contained large hail and damaging winds. CAPE values were in the range of 500-1000 J/kg along with steep lapse rates around 8.5+ C/km with freezing levels near 3km AGL.

Hail in SWEET GRASS, MONTANA
From 02-JUL-18 17:44:00 to 02-JUL-18 17:44:00 (MST-7)
Location: GREYCLIFF
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in STILLWATER, MONTANA
From 02-JUL-18 17:57:00 to 02-JUL-18 17:57:00 (MST-7)
Location: ABSAROKEE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in YELLOWSTONE, MONTANA
From 02-JUL-18 18:40:00 to 02-JUL-18 18:40:00 (MST-7)
Location: POMPEYS PILLAR
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Hail in STILLWATER, MONTANA
From 02-JUL-18 18:01:00 to 02-JUL-18 18:01:00 (MST-7)
Location: ABSAROKEE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in YELLOWSTONE, MONTANA
From 02-JUL-18 19:02:00 to 02-JUL-18 19:02:00 (MST-7)
Location: LAUREL
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in STILLWATER, MONTANA
From 02-JUL-18 19:30:00 to 02-JUL-18 19:30:00 (MST-7)
Location: PARK CITY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in TREASURE, MONTANA
From 02-JUL-18 19:30:00 to 02-JUL-18 19:30:00 (MST-7)
Location: MYERS
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Hail in TREASURE, MONTANA
From 02-JUL-18 19:32:00 to 02-JUL-18 19:32:00 (MST-7)
Location: MYERS
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail was the size of quarters to golf balls.

Hail in ROSEBUD, MONTANA
From 02-JUL-18 19:55:00 to 02-JUL-18 19:55:00 (MST-7)
Location: VANANDA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in ROSEBUD, MONTANA
From 02-JUL-18 20:09:00 to 02-JUL-18 20:09:00 (MST-7)
Location: FORSYTH
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in ROSEBUD, MONTANA
From 02-JUL-18 20:14:00 to 02-JUL-18 20:14:00 (MST-7)
Location: FORSYTH
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in BIG HORN, MONTANA
From 02-JUL-18 20:16:00 to 02-JUL-18 20:16:00 (MST-7)
Location: HARDIN AIRPARK
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Eight inch diameter tree limbs were broken.

Hail in BIG HORN, MONTANA
From 02-JUL-18 20:16:00 to 02-JUL-18 20:16:00 (MST-7)
Location: HARDIN AIRPARK
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in ROSEBUD, MONTANA
From 02-JUL-18 20:19:00 to 02-JUL-18 20:19:00 (MST-7)
Location: FORSYTH
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Hail in ROSEBUD, MONTANA
From 02-JUL-18 20:19:00 to 02-JUL-18 20:19:00 (MST-7)
Location: FORSYTH
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Hail in ROSEBUD, MONTANA
From 02-JUL-18 20:26:00 to 02-JUL-18 20:26:00 (MST-7)
Location: FORSYTH
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in ROSEBUD, MONTANA
From 02-JUL-18 20:30:00 to 02-JUL-18 20:30:00 (MST-7)
Location: FORSYTH ARPT
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Hail in CUSTER, MONTANA
From 02-JUL-18 20:34:00 to 02-JUL-18 20:34:00 (MST-7)
Location: MILES CITY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CUSTER, MONTANA
From 02-JUL-18 20:42:00 to 02-JUL-18 20:42:00 (MST-7)
Location: MILES CITY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in BIG HORN, MONTANA
From 02-JUL-18 21:00:00 to 02-JUL-18 21:00:00 (MST-7)
Location: KIRBY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in ROSEBUD, MONTANA
From 02-JUL-18 21:00:00 to 02-JUL-18 21:00:00 (MST-7)
Location: HATHAWAY
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Hail in ROSEBUD, MONTANA
From 02-JUL-18 21:25:00 to 02-JUL-18 21:25:00 (MST-7)
Location: LAME DEER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in CUSTER, MONTANA
From 02-JUL-18 21:30:00 to 02-JUL-18 21:30:00 (MST-7)
Location: FT KEOGH
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CUSTER, MONTANA
From 02-JUL-18 21:40:00 to 02-JUL-18 21:40:00 (MST-7)
Location: MILES CITY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Thunderstorm Wind in CUSTER, MONTANA
From 02-JUL-18 22:30:00 to 02-JUL-18 22:30:00 (MST-7)
Location: MIZPAH
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Hail in FALLON, MONTANA
From 02-JUL-18 22:53:00 to 02-JUL-18 22:53:00 (MST-7)
Location: PLEVNA
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in FALLON, MONTANA
From 02-JUL-18 22:58:00 to 02-JUL-18 22:58:00 (MST-7)
Location: BAKER ARPT
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in FALLON, MONTANA
From 02-JUL-18 23:15:00 to 02-JUL-18 23:15:00 (MST-7)
Location: BAKER
Magnitude: 60.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Several trailers were blown over including a fireworks trailer. There was also brick damage to the top of a building.

Thunderstorm Wind in CARTER, MONTANA
From 02-JUL-18 23:29:00 to 02-JUL-18 23:29:00 (MST-7)
Location: MILL IRON
Magnitude: 61.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in FALLON, MONTANA
From 02-JUL-18 23:40:00 to 02-JUL-18 23:40:00 (MST-7)
Location: OLLIE
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in FALLON, MONTANA
From 03-JUL-18 00:02:00 to 03-JUL-18 00:02:00 (MST-7)
Location: WEBSTER
Magnitude: 61.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tree limbs 12 inches in diameter were broken out of trees.

Hail in YELLOWSTONE, MONTANA
From 02-JUL-18 19:12:00 to 02-JUL-18 19:12:00 (MST-7)
Location: LAUREL
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public