High-Impact Weather and Climate Events

The driest calendar year on record for Wyoming, with 69% of normal precipitation. Spring and summer were especially dry, at 55% of normal. Livestock producers were heavily impacted.

A downslope windstorm along the Wasatch Front with winds of 60-80 mph. The peak gust of 102 mph recorded in Centerville. The majority of damage occured between North Salt Lake and South Ogden. Winds caused $4 million in infrastructure damage, almost entirely in Davis County, destroying hundreds of trees, powerlines, street signs and light poles. Private insured losses in Davis County alone were estimated at $64 million, mostly damage to glass, roofs, and fences. Additionally, 11 semi-trailers were knocked over on I-15. Damages resulted from wind directly and also from flying debris.

The most costly hailstorm in Wyoming history. Hail up to 2" in diameter covered most of Cheyenne, with accompanying rain totalling 1.46" of precipitation. Widespread damage to buildings and cars.

Slide blocked Highway 89, forcing Afton residents to detour 75 miles through Idaho to get to Jackson.

Virgin River Flood. "In 2010, a widespread, long duration rainfall event continued for 4 straight days. The North Fork Virgin River, which has a base flow rate of 100 cubic feet per second, rose to 6,000 cubic feet per second during this event. The Virgin River near the town of St. George recorded flows rising from 100 cubic feet per second to 25,000 cubic feet per second in a 24-hour period. Zion National Park was heavily damaged due to the flooding. The town of Washington also reported widespread flooding." - National Weather Service

The Fourmile Canyon Fire started after a month of extremely dry conditions, on a day with unusually strong winds for early September. Most of the 169 homes destroyed were burned on the first day of spread. About 6,500 acres were burned, and the city of Boulder itself was at risk on September 10.

A severe thunderstorm produced hail up to around golf-ball size in Gillette, causing extensive damage across the city. The storm moved generally from south to north through the city. The most heavily damaged areas were in the Westover Hills and Foothills subdivisions, as well as the downtown area. The hail damaged the roofs and windows of several thousand homes and buildings. Thousands of automobiles were damaged across the city.

A line of severe thunderstorms with damaging winds dropped large hail over a swath of the Denver metro area and spawned two weak tornadoes.

"A powerful tornado swept north-northwestward across Weld County and into Larimer County, carving a path of destruction, nearly 39 miles in length. The tornado, up to one-mile wide at times, initially touched down northeast of Platteville and finally lifted 6 miles west-northwest of Wellington. A tornado assessment in the aftermath of the tornado revealed extensive areas of damage. On the enhanced Fujita Scale there were pockets of EF3 damage, mainly near the Missile Silo Park Campground, and to businesses and homes in eastern Windsor. 
There was one fatality, and 78 injuries. One man was killed when he tried to escape the trailer park in his motor home. Preliminary estimates from FEMA indicated 850 homes were damaged, and nearly 300 homes were significantly damaged or destroyed. Privately insured damages totaled $147 million, and the Poudre Valley Rural Electric Associated reported $1 million of damage to electric transmission lines." - NWS

The Milford Flat Fire was the largest wildfire in Utah's history, burning 363,000 acres. The fire was ignited by dry thunderstorms and took place in cheatgrass, sagebrush, and pinyon-juniper stands. The fire destroyed rangeland in Millard and Beaver Counties killing cattle, burning four buildings and a cabin. Large stretches of I-15 were closed during the fire. Two people were killed in a fire-related motorcycle accident.