A weak surface low pressure system, including a cold front, a dryline, an ejecting upper level disturbance, and a moderately unstable atmosphere allowed strong thunderstorms to develop and become severe as they moved eastward through eastern Montana.

Hail in PRAIRIE, MONTANA
From 28-AUG-13 18:59:00 to 28-AUG-13 18:59:00 (MST-7)
Location: BLATCHFORD
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter estimated half dollar sized hail.

Hail in PRAIRIE, MONTANA
From 28-AUG-13 19:47:00 to 28-AUG-13 19:47:00 (MST-7)
Location: BLATCHFORD
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter estimated hail up to size of quarters.

Hail in MCCONE, MONTANA
From 28-AUG-13 19:58:00 to 28-AUG-13 19:58:00 (MST-7)
Location: COW CREEK DOT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported hail up to the size of quarters.

Thunderstorm Wind in PRAIRIE, MONTANA
From 28-AUG-13 20:25:00 to 28-AUG-13 20:25:00 (MST-7)
Location: MILDRED
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported shingles ripped from a roof.

Hail in GARFIELD, MONTANA
From 28-AUG-13 17:30:00 to 28-AUG-13 17:30:00 (MST-7)
Location: COHAGEN
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained Spotter reported walnut-sized hail.

Hail in GARFIELD, MONTANA
From 28-AUG-13 17:40:00 to 28-AUG-13 17:40:00 (MST-7)
Location: COHAGEN
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Cooperative observer reported half dollar sized hail.

Thunderstorm Wind in ROOSEVELT, MONTANA
From 28-AUG-13 20:35:00 to 28-AUG-13 20:35:00 (MST-7)
Location: WOLF PT INTL AIRPORT(KOLF)
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported wind gusts of 60 mph.

Thunderstorm Wind in MCCONE, MONTANA
From 28-AUG-13 19:30:00 to 28-AUG-13 19:30:00 (MST-7)
Location: BROCKWAY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported wind gusts of 60 mph.

Thunderstorm Wind in DAWSON, MONTANA
From 28-AUG-13 21:20:00 to 28-AUG-13 21:20:00 (MST-7)
Location: BLOOMFIELD
Magnitude: 57.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter measured a 66 mph wind gust.

Hail in PRAIRIE, MONTANA
From 28-AUG-13 20:25:00 to 28-AUG-13 20:25:00 (MST-7)
Location: MILDRED
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter estimated quarter-sized hail and reported heavy rain.

Thunderstorm Wind in GARFIELD, MONTANA
From 28-AUG-13 15:45:00 to 28-AUG-13 15:45:00 (MST-7)
Location: JORDAN AIRPORT (KJDN)
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported dead cottonwood tree blown down and grain auger blown over 4 miles SSW of the Hell Creek Recreation Area.

Thunderstorm Wind in PRAIRIE, MONTANA
From 28-AUG-13 19:30:00 to 28-AUG-13 19:30:00 (MST-7)
Location: SUTHERLAND
Magnitude: 52.00 EG
Crop damage: 0.00K
Reported by: Law Enforcement

Prairie County Dispatch reported extensive property damage to windows, siding, and trees from winds and hail.