Debris Flow in Wyoming
Every debris flow event the National Weather Service has filed in Wyoming, year by year, with the most significant episodes. A fast-moving slurry of mud, rock and debris, usually on a slope soaked by heavy rain or stripped by a fire.
The most significant on the map
The most significant debris flow episodes in Wyoming.
- Tornadoes
- Tropical storms and surge
- Floods
- Wind
- Hail
- Winter weather
- Heat and drought
- Cold
- Fire, smoke and dust
- Marine and coastal
- Other
The record
- Events
- 7
- Deaths
- 0
- Injuries
- 0
- Damage
- $1.2 million
Every year
The most significant
Ranked by deaths, injuries, damage and size together.
- Debris Flow in Wyoming, May 14 to 25, 2011Mud and debris began flowing onto US Highway 26/89 near milepost 127 in the Snake River Canyon on Saturday morning, May 14, as a result of rapid snowmelt in the area of Double Draw.
- Debris Flow in Wyoming, July 18, 2004A thunderstorm produced very heavy rain late in the evening over Sylvan Pass. A slide of mud and earth oozed onto U.S. Highway 16 about 6 miles west of Yellowstone National Park's east entrance. Four feet of mud and debris trapped sixteen people in four vehicles for three hours.
- Debris Flow in Wyoming, April 18, 2011A rockslide on US Highway 14A east of Lovell in the Bighorn Mountains deposited at least 7,500 cubic yards of rock on the roadway. The slide occurred near milepost 73.4 and was witnessed and recorded by at least one person.
- Debris Flow in Wyoming, June 10 to 13, 2011The melting of record snowpack combined with heavy rain to saturate soils in the western Bighorn Mountains. Land below a section of U.S. Highway 14 above Shell Falls gave way near milepost 31.5 making travel on the highway unsafe.
- Debris Flow in Wyoming, June 14, 2011Melting of a substantial late-season snowpack caused mud and debris to flow across the Upper Hoback River Road in far west Sublette County. The flow occurred at mile 14 of the road and was several feet deep.
- Debris Flow in Wyoming, August 1, 2019A heavy rain and hailstorm caused a mudslide in Hoback Canyon. The mud and rockslide closed US 26/89 for several hours. Several vehicles were blocked between the slides. Plows had to be called out to clear the road.
- Debris Flow in Wyoming, July 15, 2025At least 4 debris flows within the Elk Burn Scar occurred along US-14 that closed the road for 3-4 hours. Also caused a log jam along the Little Tongue Canyon on Little Tongue Ranch, which caused localized flooding and damage to a barn. 0.7 inches of rain fell from 7 to 7:30pm.
More
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.