Hail, Golden Valley
- When
- August 15, 12:55 AM MST
- Where
- Golden Valley County, Lavina
- Measured
- 1 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.280, -108.930
Quarter size hail reported.
Tornadoes and Hail in Montana, August 15, 1999
16 hail, 3 funnel cloud, 2 tornado, 1 thunderstorm wind, as filed by the National Weather Service.
Where it happened
Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
- Tornadoes
- Tropical storms and surge
- Floods
- Wind
- Hail
- Winter weather
- Heat and drought
- Cold
- Fire, smoke and dust
- Marine and coastal
- Other
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 22
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The radar
The Billings radar (KBLX), 54 km away, was scanning. The volume nearest the first event began at 07:53 UTC.
Event by event
16 hail, 3 funnel cloud, 2 tornado, 1 thunderstorm wind. Local standard time, as filed.
Hail, Musselshell
- When
- August 15, 1:40 AM MST
- Where
- Musselshell County, 8 mi SW of Roundup
- Measured
- 1.25 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.370, -108.650
Half dollar size hail reported.
Funnel Cloud, Golden Valley
- When
- August 15, 1:44 AM MST
- Where
- Golden Valley County, Lavina
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.381, -109.175 (the zone’s center; the record gives no point)
Funnel clouds were reported near Lavina.
Hail, Golden Valley
- When
- August 15, 1:50 AM MST
- Where
- Golden Valley County, Lavina
- Measured
- 2.75 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.280, -108.930
Baseball size hail reported.
Hail, Musselshell
- When
- August 15, 2:00 AM MST
- Where
- Musselshell County, Roundup
- Measured
- 1 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.450, -108.530
Silver Dollar size hail reported.
Hail, Stillwater
- When
- August 15, 2:05 AM MST
- Where
- Stillwater County, 8 mi NNW of Rapelje
- Measured
- 0.75 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.070, -109.330
Dime size hail reported.
Hail, Golden Valley
- When
- August 15, 2:25 AM MST
- Where
- Golden Valley County, 5 mi SW of Lavina
- Measured
- 1.75 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.230, -109.000
Golf ball size hail reported.
Hail, Musselshell
- When
- August 15, 3:05 AM MST to 3:12 AM MST
- Where
- Musselshell County, Roundup to 12 mi E of Roundup
- Measured
- 0.75 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.280, -108.530
Dime size hail reported near Roundup.
Hail, Treasure
- When
- August 15, 5:40 AM MST
- Where
- Treasure County, Hysham
- Measured
- 0.75 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.300, -107.230
Dime size hail reported.
Thunderstorm Wind, Rosebud
- When
- August 15, 6:11 AM MST
- Where
- Rosebud County, 5 mi NNW of Forsyth
- Measured
- 50 kt (58 mph)
- Reported by
- TRAINED SPOTTER
- Coordinates
- 46.330, -106.700
58 mph wind gust reported.
Hail, Carbon
- When
- August 15, 9:50 AM MST
- Where
- Carbon County, Joliet
- Measured
- 0.75 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 45.480, -108.980
Dime size hail reported.
Funnel Cloud, Yellowstone
- When
- August 15, 10:10 AM MST
- Where
- Yellowstone County, Billings
- Reported by
- NWS EMPLOYEE(OFF DUTY)
- Coordinates
- 45.937, -108.274 (the zone’s center; the record gives no point)
A funnel cloud was spotted in southwest Billings by an off-duty National Weather Service employee.
Hail, Rosebud
- When
- August 15, 10:15 AM MST
- Where
- Rosebud County, 15 mi N of Forsyth
- Measured
- 1.5 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 46.480, -106.670
Spotter report of silver dollar size hail.
Funnel Cloud, Yellowstone
- When
- August 15, 10:20 AM MST
- Where
- Yellowstone County, 3 mi SE of Billings
- Reported by
- GENERAL PUBLIC
- Coordinates
- 45.937, -108.274 (the zone’s center; the record gives no point)
Several funnel clouds were spotted southeast of Billings.
Hail, Big Horn
- When
- August 15, 10:55 AM MST
- Where
- Big Horn County, Yellowtail
- Measured
- 0.75 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.330, -107.920
Spotter report of dime size hail.
Hail, Big Horn
- When
- August 15, 11:00 AM MST
- Where
- Big Horn County, 1 mi W of Hardin
- Measured
- 0.88 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.730, -107.620
Spotter report of nickel size hail.
Tornado, Rosebud
- When
- August 15, 11:25 AM MST
- Where
- Rosebud County, 16 mi W of Ingomar
- Rating
- F0
- Path length
- 0.1 mi
- Path width
- 5 yd
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.580, -107.700
Brief touchdown reported by Rosebud County Sheriff.
Hail, Custer
- When
- August 15, 11:45 AM MST
- Where
- Custer County, 14 mi N of Miles City
- Measured
- 0.75 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 46.600, -105.830
Spotter report of dime size hail.
Hail, Treasure
- When
- August 15, 11:50 AM MST
- Where
- Treasure County, 8 mi SE of Hysham
- Measured
- 0.75 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 46.220, -107.120
Spotter report of dime size hail.
Tornado, Rosebud
- When
- August 15, 12:15 PM MST
- Where
- Rosebud County, 10 mi W of Forsyth
- Rating
- F0
- Path length
- 0.1 mi
- Path width
- 5 yd
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 46.270, -106.880
Brief touchdown reported by Rosebud County Sheriff.
Hail, Powder River
- When
- August 15, 1:20 PM MST to 1:30 PM MST
- Where
- Powder River County, Broadus to 15 mi of Powderville
- Measured
- 1 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.670, -105.420
Spotter reports of quarter size hail in northern Powder River County.
Hail, Carter
- When
- August 15, 2:00 PM MST
- Where
- Carter County, 6 mi SE of Ekalaka
- Measured
- 1.25 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.820, -104.470
Spotter report of half dollar size hail.
What these are
- Hail
- Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
- Funnel Cloud
- A rotating column of cloud extending from a thunderstorm that did not reach the ground.
- Thunderstorm Wind
- Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
- Tornado
- A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Tornadoes and Hail in North Dakota, August 15, 1999
- Tornado in North Dakota, August 15, 1999
- Hail in North Dakota, August 15, 1999
- Hail in North Dakota, August 15, 1999
- Tornado in North Dakota, August 15, 1999
- Hail and Damaging Winds in Nebraska, August 15, 1999
- Damaging Wind in North Dakota, August 15, 1999
- Tornado in North Dakota, August 15, 1999
- Lightning Strike in Florida, August 15, 1999
- Hail in Montana, August 15, 1999
- Hail in Minnesota, August 15, 1999
- Damaging Wind in Minnesota, August 15, 1999
More
Every storm in Montana in 1999Every state in 1999This day in weather historyThe tornado archive for Montana, 1999Warnings in Montana, August 1999
Sources
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5710987, 5710988, 5710989, 5710990, 5710991, 5710992, 5710993, 5711067, 5711068, 5711069, 5711070, 5711071, 5711072, 5711073, 5711074, 5711075, 5711076, 5711077, 5711078, 5711079, 5711080, 5711081.