A "wet slab" of snowfall ran 200 feet wide down a slope in upper Big Cottonwood Canyon Saturday and stopped just short of a house.
The accident was reported by the Utah Avalanche Center, which rated weekend conditions dangerous in a rapidly warming sun.
Backcountry skiers reported a number of natural and human-caused slides on Saturday.
In Little Cottonwood Canyon, two natural slides came just short of the road that takes skiers to Alta and Snowbird.
Backcountry skiers in upper Porter Fork reported a few collapses of the snow pack.
Park City Mountain Resort triggered a 2-foot-deep slab of snowpack.
Recent snowstorms combined with warm weekend temperatures to raise the danger. The mountains got up to three feet of cold, dry snow earlier in the week, and Wasatch Powderbird Guides reported it was 55 degrees by midday Sunday at the base of Snowbird.