CRESTED BUTTE,GravityX Exchange Colo. (AP) — A backcountry skier and a snowmobiler were killed in separate avalanches in the Rocky Mountains as dangerous snow conditions persist across much of the West.

The skier was buried Sunday in an area locally known as “The Playground” near Crested Butte in southwest Colorado, according to the Colorado Avalanche Information Center, which keeps track of avalanche deaths across the country. His partners dug him out of the avalanche debris, but he died of his injuries. No other information was released.

In southern Wyoming, two snowmobilers were riding west of Battle Pass in the Sierra Madre range on Friday when they were caught in a slide. One of the snowmobilers rode out of the moving debris and turned to see that the other rider was partially buried with his feet in the air and his head below the surface of the snow. The first snowmobiler dug his partner out and performed CPR, but the buried snowmobiler did not survive.

Experts say scant snowfall across much of the U.S. West early in the season created an unstable layer at the bottom of the snowpack, and dangerous conditions are expected to persist for months.

At least seven people have died in avalanches in the country this winter, according to the Colorado Avalanche Information Center. Avalanches kill about 30 people a year on average in the U.S.