ASPEN - Up to 25 inches of fresh snow as of Tuesday morning sent the avalanche danger soaring in the Marble and McClure Pass areas as well as around Sunlight Mountain outside Glenwood Springs, according to the Colorado Avalanche Information Center.
The avalanche danger was "high" on the west side of the Aspen zone, according to Brian McCall, a forecaster with the avalanche center. The swath with the highest danger includes Marble, Schofield Pass and Sunlight. The slopes facing north, northeast and east that are near and above treeline have the high rating, McCall wrote.
The danger elsewhere in the Aspen zone is considerable. Lower snowfall totals accumulated outside the Marble area, but backcountry areas picked up 7 to 12 inches.
That new snow is piling up on old, weak layers in the snowpack, creating potentially dangerous conditions, according to McCall.
"Avalanches that start in the upper snowpack have the potential to step down to several layers of older, persistent slabs in the middle of the snowpack," McCall wrote. "Once triggered, you could see avalanches running on weak layers near the ground."
More snow is forecast to add to the weak layers through Thursday.
The snowfall that's making conditions dicey in the backcountry finally made for premium conditions at the Aspen-Snowmass ski areas. Aspen Skiing Co. reported 7 inches of snow at Snowmass over a 24-hour period ending Tuesday morning. Buttermilk and Aspen Highlands picked up 6 inches while Aspen Mountain reported 5 inches of powder as of 4 a.m. Snowmass and Aspen Highlands both hauled in 12 inches of snow over the entire storm cycle.
Sunlight Mountain Resort reported 20 inches of powder out of the storm.
Resorts in southwest Colorado got 36 to 78 inches of snow from stormy weather that started Saturday. Silverton Mountain picked up 78 inches, according to Colorado Ski Country USA, a trade group. Purgatory raked in 37 inches while Wolf Creek received 36 inches. Powderhorn, on the Grand Mesa, collected 33 inches.
Other storm totals include 26 inches at Steamboat; 23 inches at Telluride; 18 inches at Monarch; and 17 inches at Crested Butte.
The storm cycle has boosted the paltry snowpack east of Aspen to 46 percent, according to the Natural Resources Conservation Service. The highest snowpack total in the Roaring Fork River basin is 93 percent at North Lost Trail, outside Marble.