2:27pm

Fri January 27, 2012
Environment

High Country Avalanche Danger Will Continue

The Colorado Avalanche Information Center has posted an Avalanche Warning for a large portion of the state’s mountain areas through Saturday afternoon.  While the avalanche warning may expire Saturday, dangerous avalanche conditions are going to persist through the weekend.

The very dangerous backcountry conditions across Colorado’s high country actually began to take shape at the beginning of winter.

 With the very dry start to the season, the mountains saw a thin snow pack structure.  That snow pack became very weak over time.  So much so that it was not able to handle any significant snowfall.

Brian Lazar, deputy director of the Colorado Avalanche Information Center says with recent snow falling in a window of less then 12 hours (0.5 to 0.75 inches of snow water equivalent fell overnight), the weak snow pack has had little time to recover, which has put the state back into high avalanche danger through at least tomorrow.

“We’ve seen a very reactive snow pack. What we’re seeing are collapses and cracks that are often initiated from low angle or even flat terrain. Those collapses can propagate some distances.  We’ve see them propagate several 100 feet or even farther away  from where the collapse was initiated. [This] means that failure can then propagate into steeper slopes that are quite a distance away from where you are standing.”

Naturally triggered avalanches (caused by wind and snowfall) are likely today, and human triggered avalanches are very likely.

 “The storm is winding down and so we don’t expect avalanche danger to raise much beyond where it is right now.  But even if the warning expires for tomorrow, dangerous avalanche conditions are going to persist at least through the weekend, which means human triggered avalanches will remain likely all through the weekend.”

Lazar says backcountry travel on or below slopes of 30 degrees or steeper, is not recommended during the warning.

He says people have to realize that backcountry avalanche terrain is anything not mitigated and managed by snow safety teams like the ones at ski resorts.

“Just on the other side of the ski area boundary you are dealing with backcountry snow pack conditions.”

Given the nature of our current snow pack, the state’s mountains are going to be dealing with dangerous avalanche conditions for awhile. 

“What we would need to go back towards periods of low avalanche danger, is for a lot of these underlying weak layers of snow to go away and become stronger overtime.  Unfortunately given the nature of our current snow pack we’re going to be dealing with these weaknesses for the foreseeable future.”