We stumbled onto this avalanche not long after it was triggered. Details about how it was triggered are unknown. The starting zone measured 40 degrees in steepness. The fracture line was up to 4 feet deep in places. The weak layer was faceted sugar snow that formed on the surface in mid December during a dry spell. This layer was buried by the Christmas and New Year's storms as well as the very windy storm earlier this week. The layer is actually not alarmingly weak but the wind drifted snow from the past storm was enough to push it to the brink.

In the image below, you can see the other smaller avalanches that were snowmobile triggered on Tuesday, Jan 8.