Thunderstorm Wind, Yellowstone
- When
- July 20, 1:55 PM MST
- Where
- Yellowstone County, 6 mi S of Billings
- Measured
- 52 kt (60 mph)
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.720, -108.480
Spotter estimated wind gust of 60 mph.
Hail and Damaging Winds in Montana, July 20, 1999
3 thunderstorm wind, 3 hail, as filed by the National Weather Service.
Where it happened
Every event with a place to put it. 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
- $50,000
- Crop damage
- None recorded
- Events
- 6
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), 18 km away, was scanning. The volume nearest the first event began at 20:55 UTC.
Event by event
3 thunderstorm wind, 3 hail. Local standard time, as filed.
Thunderstorm Wind, Yellowstone
- When
- July 20, 2:00 PM MST
- Where
- Yellowstone County, Acton
- Measured
- 52 kt (60 mph)
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.930, -108.680
Spotter estimated wind gust of 60 mph.
Hail, Yellowstone
- When
- July 20, 2:06 PM MST
- Where
- Yellowstone County, 6 mi S of Billings
- Measured
- 1 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.720, -108.480
Spotter report of quarter size hail.
Hail, Yellowstone
- When
- July 20, 2:16 PM MST
- Where
- Yellowstone County, Huntley
- Measured
- 0.88 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.900, -108.320
Spotter report of nickel size hail.
Thunderstorm Wind, Custer
- When
- July 20, 5:30 PM MST
- Where
- Custer County, Miles City
- Property damage
- $50,000
- Reported by
- EMERGENCY MANAGER
- Coordinates
- 46.400, -105.830
Thunderstorm wind gusts of at least 48 mph caused several trees and a billboard to be blown down, a camping trailer to be blown over and some broken windows in and around Miles City.
Hail, Carter
- When
- July 20, 8:30 PM MST
- Where
- Carter County, 30 mi S of Ekalaka
- Measured
- 0.75 in hail
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.450, -104.550
Spotter report of dime size hail.
What these are
- 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.
- Hail
- Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Heat in Ohio, July 20 to 31, 1999
- Heat in Illinois, July 20 to 26, 1999
- Heat in Georgia, July 20 to 31, 1999
- Heat in North Carolina, July 20 to 31, 1999
- Drought in Iowa, July 20 to 30, 1999
- Heat in Kentucky, July 20 to 31, 1999
- Heat in South Carolina, July 20 to 31, 1999
- Flash Flooding in Iowa, July 20, 1999
- Flooding and Hail in Wisconsin, July 20, 1999
- Tornadoes and Hail in Iowa, July 20, 1999
- Flash Flooding and Damaging Wind in Iowa, July 20 to 21, 1999
- Flash Flooding in Minnesota, July 20, 1999
More
Every storm in Montana in 1999Every state in 1999This day in weather historyWarnings in Montana, July 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 2026-09-30. Each event’s entry at NCEI: 5708621, 5708624, 5708622, 5708623, 5708625, 5708626.