During the late afternoon and evening of June 16, 2007, a high precipitation supercell thunderstorm tracked from across northern Montana, just to the north of a warm front.  This was the most devastating hail storm to affect the area since at least 1999, and prompted 22 severe thunderstorm and 6 tornado warnings in the NWS Glasgow county warning area. The storm began early in the day just east of Glacier National Park and gradually moved hundreds of miles eastward through the day.  By 3 pm, the storm crossed into the NWS Glasgow area in Phillips County, where it started to make a turn to the southeast.   The storm traveled for over 250 miles before decreasing in Richland County near the North Dakota border a little after 11 pm.  Hail up to baseball size and wind gusts in excess of 85 mph accompanied the storm.  Torrential heavy rainfall was also experienced, prompting seven flash flood warnings to be issued.  The large hail left a hail swath seen on GOES and Terra MODIS satellites that had a path at least 225 miles long, and up to 12 miles wide.
The most significant damage from the storm occurred in portions of Valley and McCone Counties.  The towns of Glasgow and Nashua, both in Valley County, took a direct hit from the storm.  In Glasgow, southeast winds gusting to 60 to 65 mph ahead of the storm switched into the northwest with gusts in excess of 70 mph.  Golfball to baseball sized hail fell for several minutes before diminishing to penny sized for another 10-20 minutes.  The majority of the homes and businesses in Glasgow had some sort of damage including:  broken windows, damaged shingles, dented or broken gutters and skirting.  Many vehicles also had significant hail damage.  Just the property damage alone in Glasgow was nearly $8.0 million dollars.  As the storm continued east it hit the town of Nashua and every home and business had some form of damage from the baseball size hail and the damaging winds that occurred with it.   The winds were measured at 89 mph just west of town.  Property damage was estimated to be $3 million dollars.

In rural areas outside of Glasgow and Nashua there were several cottonwood trees completely uprooted.  Horses and cattle were injured by the hail and wind, and Montana Fish, Wildlife and Parks reported many birds and small animals were killed by the hail.  There were thousands of acres of alfalfa, wheat, and corn that were completely destroyed.  At this time, damage estimates to crops in Valley County are at $20 million dollars.
The storm also produced heavy rainfall of 1 to 2 inches, and was followed later in the evening by additional heavy rain.  Rainfall of 2 to 7 inches fell in the Antelope, Brazil and Willow Creek basins.  The Antelope Creek basin had its most significant flood on record and one road was completely underwater for nearly a third of a mile.  One ranch was isolated by the flood waters for three days.
As the storm continued across northern McCone County and into western Richland County it continued to produce hail up to the size of ping pong balls and wind gusts that were estimated as high as 80 to 90 mph knocked down telephone and electrical poles.   There was significant damage to farms and ranches in the Vida area, as well as significant loss of crops, estimated at $5 million dollars.  The rural nature of the area minimized the property damage that could have occurred.
The overall estimated damage in this storm between the hail and wind damage, and the subsequent flooding is 34.2 million dollars.

Thunderstorm Wind in VALLEY, MONTANA
From 16-JUN-07 17:05:00 to 16-JUN-07 17:05:00 (MST-7)
Location: GLASGOW
Magnitude: 70.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Two to three foot diameter cottonwood trees were uprooted.  Windows were blown out of homes.  See entire episode narrative for full details.

Thunderstorm Wind in VALLEY, MONTANA
From 16-JUN-07 17:20:00 to 16-JUN-07 17:20:00 (MST-7)
Location: NASHUA
Magnitude: 80.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

One hundred percent of the businesses and homes in the town were damaged from the combination of large hail and damaging winds.  Many vehicles also had significant damage.  Damages included roofing, windows, gutters, siding, trees and gardens.  Damage amounts in Nashua to property are estimated at 3 millions dollars.  See entire episode narrative for full details.

Hail in VALLEY, MONTANA
From 16-JUN-07 17:20:00 to 16-JUN-07 17:30:00 (MST-7)
Location: NASHUA
Magnitude: 2.75 
Property damage: 3.00M
Crop damage: 5.00M
Reported by: NWS Storm Survey

One hundred percent of the businesses and homes in the town were damaged from the combination of large hail and damaging winds.  Many vehicles also had significant damage.  Damages included roofing, windows, gutters, siding, trees and gardens.  See entire episode narrative for full details.

Flash Flood in RICHLAND, MONTANA
From 16-JUN-07 23:00:00 to 17-JUN-07 01:00:00 (MST-7)
Location: ENID
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Three and a half inches of storm total rainfall caused water to run over dams in the area.

Flash Flood in VALLEY, MONTANA
From 16-JUN-07 23:30:00 to 17-JUN-07 11:00:00 (MST-7)
Location: GLASGOW
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Two to seven inches of rain fell in the Antelope, Brazil and Willow Creek Basins and caused the worst flood on record on the Antelope Creek.  A portion of Billingsly road was inaccessible and completely under water for 3 days.  Flash flooding occurred for approximately 12 hours, but was followed by significant overland flooding for the following few to several days.

Thunderstorm Wind in MCCONE, MONTANA
From 16-JUN-07 18:45:00 to 16-JUN-07 18:45:00 (MST-7)
Location: VIDA
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

See entire episode narrative for full details.

Hail in MCCONE, MONTANA
From 16-JUN-07 18:50:00 to 16-JUN-07 18:50:00 (MST-7)
Location: VIDA
Magnitude: 1.00 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Public

The hail ranged in size from nickel to quarter and covered the ground.  Two windows were blown out on the west side of a home along with some damge to the siding.  See entire episode narrative for full details.

Hail in RICHLAND, MONTANA
From 16-JUN-07 18:55:00 to 16-JUN-07 18:55:00 (MST-7)
Location: SIDNEY
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The hail covered the ground and was accompanied by wind of 50 to 60 mph.  See entire episode narrative for full details.

Hail in RICHLAND, MONTANA
From 16-JUN-07 19:20:00 to 16-JUN-07 19:20:00 (MST-7)
Location: ENID
Magnitude: 1.00 
Property damage: 50.00K
Crop damage: 1.00M
Reported by: Trained Spotter

Nickel to quarter hail covered the ground. Thunderstorm winds estimated at  80 mph accompanied the hail and caused significant crop damage and some damage to windows and roofs on area farms.  See entire episode narrative for full details.

Thunderstorm Wind in RICHLAND, MONTANA
From 16-JUN-07 19:20:00 to 16-JUN-07 19:20:00 (MST-7)
Location: ENID
Magnitude: 70.00 EG
Reported by: Public

The wind was estimated at 80 to 90 mph.  Several windows and screens were destroyed on the west side of the house.  The steel siding was lost off of a home.  Crop damage was reported as being extensive.  See entire episode narrative for full details.

Hail in VALLEY, MONTANA
From 16-JUN-07 16:50:00 to 16-JUN-07 17:05:00 (MST-7)
Location: GLASGOW
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

One and half inch hail fell for about 4 minutes and then penny sized hail lasted an additional 10-11 minutes.  Winds estimated at 70 mph combined with the hail caused significant damage.  See entire episode narrative for full details.

Hail in VALLEY, MONTANA
From 16-JUN-07 16:50:00 to 16-JUN-07 17:10:00 (MST-7)
Location: GLASGOW
Magnitude: 3.00 
Property damage: 8.00M
Crop damage: 15.00M
Reported by: NWS Storm Survey

Hail up to three inches in size accompanied by winds around 70 mph caused significant damage throughout the city of Glasgow and outlying areas to the west, south and east. See entire episode narrative for full details.

Thunderstorm Wind in VALLEY, MONTANA
From 16-JUN-07 17:12:00 to 16-JUN-07 17:12:00 (MST-7)
Location: FT PECK
Magnitude: 77.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

See entire episode narrative for full details.

Hail in MCCONE, MONTANA
From 16-JUN-07 17:55:00 to 16-JUN-07 17:55:00 (MST-7)
Location: VIDA
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

See entire episode narrative for full details.

Hail in MCCONE, MONTANA
From 16-JUN-07 18:30:00 to 16-JUN-07 18:30:00 (MST-7)
Location: VIDA
Magnitude: 1.00 
Property damage: 100.00K
Crop damage: 5.00M
Reported by: Public

The hail was accompanied by 50 to 60 mph thunderstorm wind gusts.  The combination of the hail and wind led to some significant crop damage as well as structural damage to several farms.  See entire episode narrative for full details.

Hail in MCCONE, MONTANA
From 16-JUN-07 18:35:00 to 16-JUN-07 18:35:00 (MST-7)
Location: VIDA
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

See entire episode narrative for full details.

Thunderstorm Wind in RICHLAND, MONTANA
From 17-JUN-07 05:30:00 to 17-JUN-07 05:30:00 (MST-7)
Location: SIDNEY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Tree branches down in the downtown area.

Thunderstorm Wind in RICHLAND, MONTANA
From 17-JUN-07 05:30:00 to 17-JUN-07 05:30:00 (MST-7)
Location: SAVAGE
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A portable basketball goal filled with water was knocked over and damaged.

Hail in RICHLAND, MONTANA
From 17-JUN-07 05:45:00 to 17-JUN-07 05:45:00 (MST-7)
Location: CRANE
Magnitude: 1.50 
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Public

The roofs on greenhouses were damaged.

Thunderstorm Wind in DAWSON, MONTANA
From 16-JUN-07 22:40:00 to 16-JUN-07 22:55:00 (MST-7)
Location: RICHEY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in RICHLAND, MONTANA
From 16-JUN-07 23:40:00 to 16-JUN-07 23:40:00 (MST-7)
Location: ENID
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in PETROLEUM, MONTANA
From 17-JUN-07 00:30:00 to 17-JUN-07 00:50:00 (MST-7)
Location: WINNETT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The hail ranged in size from nickels to quarters.

Thunderstorm Wind in GARFIELD, MONTANA
From 17-JUN-07 01:00:00 to 17-JUN-07 01:00:00 (MST-7)
Location: SAND SPGS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in GARFIELD, MONTANA
From 17-JUN-07 02:00:00 to 17-JUN-07 02:00:00 (MST-7)
Location: VAN NORMAN
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in GARFIELD, MONTANA
From 17-JUN-07 02:30:00 to 17-JUN-07 02:30:00 (MST-7)
Location: COHAGEN
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in VALLEY, MONTANA
From 16-JUN-07 15:55:00 to 16-JUN-07 15:55:00 (MST-7)
Location: HINSDALE
Magnitude: 1.75 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Golf ball sized hail covered the ground.  Several windows were destroyed on a home.

Thunderstorm Wind in VALLEY, MONTANA
From 16-JUN-07 16:00:00 to 16-JUN-07 16:00:00 (MST-7)
Location: VANDALIA
Magnitude: 70.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

Windows were blown out on the west, north, and east side of the post office.  Glass found later embedded in wood banisters leading up to the post office entrance.

Thunderstorm Wind in VALLEY, MONTANA
From 16-JUN-07 16:38:00 to 16-JUN-07 16:38:00 (MST-7)
Location: GLASGOW
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

East winds blowing into the thunderstorm updraft were causing large tree branches to break out of poplar and cottonwood trees.

Thunderstorm Wind in MCCONE, MONTANA
From 16-JUN-07 18:30:00 to 16-JUN-07 18:30:00 (MST-7)
Location: VIDA
Magnitude: 61.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Telephone poles were down on Highway 13 at mile marker 33. Also, 13 power poles were blown down by damaging thunderstorm winds.

Thunderstorm Wind in MCCONE, MONTANA
From 16-JUN-07 18:35:00 to 16-JUN-07 18:35:00 (MST-7)
Location: VIDA
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Four inch diamter tree limbes were floating down the road in high water.

Hail in MCCONE, MONTANA
From 16-JUN-07 18:45:00 to 16-JUN-07 18:45:00 (MST-7)
Location: VIDA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The hail ranged in size from marble to quarter.

Hail in VALLEY, MONTANA
From 16-JUN-07 20:25:00 to 16-JUN-07 20:25:00 (MST-7)
Location: GLASGOW
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The hail ranged in size from penny to quarter.  The hail was accompanied by wind of 40 to 50 mph.

Hail in RICHLAND, MONTANA
From 16-JUN-07 20:35:00 to 16-JUN-07 20:35:00 (MST-7)
Location: SIDNEY
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in RICHLAND, MONTANA
From 16-JUN-07 20:35:00 to 16-JUN-07 20:35:00 (MST-7)
Location: SIDNEY
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in RICHLAND, MONTANA
From 16-JUN-07 20:42:00 to 16-JUN-07 20:42:00 (MST-7)
Location: SIDNEY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The hail covered the ground.

Flash Flood in RICHLAND, MONTANA
From 16-JUN-07 20:00:00 to 16-JUN-07 21:30:00 (MST-7)
Location: SIDNEY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Streets and fields flooding with several basements filling up with water.

Hail in VALLEY, MONTANA
From 16-JUN-07 21:30:00 to 16-JUN-07 21:30:00 (MST-7)
Location: FT PECK
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

The hail was accompanied by strong wind and 66 hundredths of an inch of rain at the Pines Recreation Area.

Flash Flood in VALLEY, MONTANA
From 16-JUN-07 23:00:00 to 16-JUN-07 23:45:00 (MST-7)
Location: GLASGOW
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Water 4 to 5 inches deep was flowing over Highway 24 near mile marker 63.

Flash Flood in RICHLAND, MONTANA
From 16-JUN-07 23:00:00 to 17-JUN-07 00:00:00 (MST-7)
Location: ENID
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Significant overland flooding with water rushing down a hill.

Hail in GARFIELD, MONTANA
From 17-JUN-07 01:14:00 to 17-JUN-07 01:18:00 (MST-7)
Location: (JDN)JORDAN
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail in MCCONE, MONTANA
From 17-JUN-07 02:45:00 to 17-JUN-07 02:45:00 (MST-7)
Location: CIRCLE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in PRAIRIE, MONTANA
From 17-JUN-07 03:20:00 to 17-JUN-07 03:20:00 (MST-7)
Location: MC CLOUD
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in DAWSON, MONTANA
From 17-JUN-07 04:15:00 to 17-JUN-07 04:15:00 (MST-7)
Location: BLOOMFIELD
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Small tree branches scattered on lawn.

Thunderstorm Wind in VALLEY, MONTANA
From 16-JUN-07 17:12:00 to 17-JUN-07 17:18:00 (MST-7)
Location: FT PECK
Magnitude: 70.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Newspaper

A power outage caused by a tree branch falling across a power line during a severe thunderstorm caused the death of 110,000 Chinook salmon fingerlings at the Fort Peck Fish Hatchery.

Hail in PHILLIPS, MONTANA
From 16-JUN-07 14:45:00 to 16-JUN-07 15:10:00 (MST-7)
Location: DODSON
Magnitude: 1.00 
Property damage: 0.00K
Reported by: Public

There was an unknown amount of crop damage.

Hail in PHILLIPS, MONTANA
From 16-JUN-07 15:28:00 to 16-JUN-07 15:28:00 (MST-7)
Location: MALTA
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The hail was accompanied by 40 to 50 mph wind.

Hail in PHILLIPS, MONTANA
From 16-JUN-07 15:45:00 to 16-JUN-07 15:45:00 (MST-7)
Location: SACO
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The hail covered the ground and was accompanied by 50 mph wind.

Hail in PHILLIPS, MONTANA
From 16-JUN-07 15:54:00 to 16-JUN-07 15:54:00 (MST-7)
Location: SACO
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail nickel to quarter size covered the ground.

Hail in PHILLIPS, MONTANA
From 16-JUN-07 15:55:00 to 16-JUN-07 15:55:00 (MST-7)
Location: BOWDOIN
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Hail in VALLEY, MONTANA
From 16-JUN-07 16:10:00 to 16-JUN-07 16:10:00 (MST-7)
Location: HINSDALE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The hail covered the ground.

Hail in VALLEY, MONTANA
From 16-JUN-07 16:32:00 to 16-JUN-07 16:32:00 (MST-7)
Location: VANDALIA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The hail ranged in size from nickel to quarter.

Hail in VALLEY, MONTANA
From 16-JUN-07 16:42:00 to 16-JUN-07 16:42:00 (MST-7)
Location: TAMPICO
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Golf ball sized hail covered 75 percent of the ground.

Thunderstorm Wind in VALLEY, MONTANA
From 16-JUN-07 16:42:00 to 16-JUN-07 16:42:00 (MST-7)
Location: TAMPICO
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Flash Flood in VALLEY, MONTANA
From 16-JUN-07 15:50:00 to 16-JUN-07 16:50:00 (MST-7)
Location: HINSDALE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm Wind in VALLEY, MONTANA
From 16-JUN-07 16:50:00 to 16-JUN-07 16:50:00 (MST-7)
Location: GLASGOW
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

A 20 foot top of a large tree was blown over by the strong wind.

Hail in VALLEY, MONTANA
From 16-JUN-07 16:47:00 to 16-JUN-07 16:47:00 (MST-7)
Location: TAMPICO
Magnitude: 1.75 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Windows broken out on the west side of a house.