A snowmobiler saw this natural avalanche hit the Daisy Pass road within 10 minutes of riding by. He did a beacon search on the debris to confirm no one had been caught. It occurred about noon. This path is not very visible from the bottom and is not one that runs regularly. It killed a rider who was on the road in February 2012. The accident report has good photos of the path from afar.
Wind-loading in the start zone was the likely trigger since skiers and sledders do not access it.
From an email: "The crown was hard to see, but only looked a few feet deep where I could see it, but the debris pile was 10'+ on the road."
A big thanks to Dan Wykoff for providing the story and pictures.