Unstable Conditions at Lionhead

Unstable Conditions at Lionhead

Date
Activity
Snowmobiling

We rode from Buttermilk past Ski Hill to the lowest portion of Lionhead Ridge, where the cornice line transitions to the wind-loaded rollover. There is a lot of new snow, and while there are still plenty of landmines, the riding is getting pretty good. No collapsing or cracking was observed. We dug on the northeast aspect on this mid/upper elevation slope and found the same persistent weak layer of concern buried 2.5 feet deep (Fist hardness surface hoar and facets). I was surprised by how sensitive this interface seemed given the depth (ECTP13). 

We then rode down and around to Denny Creek and up the local route to the lower meadow, where you first break out of the trees. We dug a second pit at the top of the first hill. Same story on this southeast aspect at 7900.' Fist hard facets and surface hoar buried 2.5 feet deep, ECTP13, no cracking or collapsing observed. 

I do not trust this snowpack. It is weak, it is failing with relatively small force given its depth, and the problematic snowpack structure seems to exist on every slope I have assessed this season in the Lionhead area. You might not trigger a slide on every steep slope right now, but you wouldn't need to ride many before triggering an avalanche. The structure seems uniform enough that remote-triggered slides are in play.

The CONSIDERABLE danger seems spot on with human-triggered avalanches likely on slopes steeper than 30 degrees. A forecast with continued snowfall will keep this snowpack on edge. 

Region
Lionhead Range
Location (from list)
LIONHEAD AREA
Observer Name
Dave Zinn