A moist surface layer feeding into the region from the southeast combined with an upper-level disturbance and moderate instability to produce many severe thunderstorms.

Hail in VALLEY, MONTANA
From 25-MAY-13 18:01:00 to 25-MAY-13 18:06:00 (MST-7)
Location: SAINT MARIE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported quarter-sized hail.

Hail in WIBAUX, MONTANA
From 25-MAY-13 06:30:00 to 25-MAY-13 06:30:00 (MST-7)
Location: BEAVER HILL DOT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported hail the size of quarters.

Hail in RICHLAND, MONTANA
From 25-MAY-13 07:23:00 to 25-MAY-13 07:23:00 (MST-7)
Location: SAVAGE
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported nickel-sized hail and estimated wind gusts of 30 mph.

Hail in MCCONE, MONTANA
From 25-MAY-13 19:05:00 to 25-MAY-13 19:05:00 (MST-7)
Location: BROCKWAY
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.

Flash Flood in VALLEY, MONTANA
From 25-MAY-13 18:25:00 to 25-MAY-13 19:55:00 (MST-7)
Location: GLASGOW
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported flooding at the Shady Rest trailer park near the East Side Elementary school and the Reynold's grocery store in Glasgow, both with 12 inches of standing water.  Public also reported water backed-up and flooding the underpass between Albertson's grocery store and Valley Bank.

Hail in VALLEY, MONTANA
From 25-MAY-13 16:10:00 to 25-MAY-13 16:10:00 (MST-7)
Location: DUCK CREEK
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported penny-sized hail.

Hail in MCCONE, MONTANA
From 25-MAY-13 16:30:00 to 25-MAY-13 16:30:00 (MST-7)
Location: FT PECK LAKE HANDAR
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported quarter-sized hail.

Hail in VALLEY, MONTANA
From 25-MAY-13 16:55:00 to 25-MAY-13 16:55:00 (MST-7)
Location: GLASGOW INTL AIRPORT (KGGW)
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported walnut-sized hail.

Hail in MCCONE, MONTANA
From 25-MAY-13 17:20:00 to 25-MAY-13 17:20:00 (MST-7)
Location: FT PECK LAKE HANDAR
Magnitude: 2.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

A National Weather Service employee reported tennis ball-sized hail.

Hail in VALLEY, MONTANA
From 25-MAY-13 17:45:00 to 25-MAY-13 17:45:00 (MST-7)
Location: BAYLOR
Magnitude: 3.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported tea cup-sized hail and over 1 inch of rain.

Hail in GARFIELD, MONTANA
From 25-MAY-13 18:00:00 to 25-MAY-13 18:00:00 (MST-7)
Location: HAXBY POINT
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported golf ball-sized hail.

Hail in GARFIELD, MONTANA
From 25-MAY-13 18:13:00 to 25-MAY-13 18:13:00 (MST-7)
Location: HAXBY POINT
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported half dollar-sized hail.

Hail in MCCONE, MONTANA
From 25-MAY-13 18:15:00 to 25-MAY-13 18:15:00 (MST-7)
Location: FT PECK LAKE HANDAR
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported golf ball-sized hail.

Hail in VALLEY, MONTANA
From 25-MAY-13 17:49:00 to 25-MAY-13 18:20:00 (MST-7)
Location: GLASGOW
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

NWS employee reported hail up to 8 inches deep in places on the west end of Glasgow. The hail was all less than 1 in size but it came down in two waves, the first just pea size hail and then a break and then larger hail to penny size that started accumululating and covering roads, parking lots and yards.