Avalanche at Cayoosh North Glacier

Big grade 3.5 Avalanche at the North Glacier of Cayoosh. Appeared to be a few days old from or just after the last storm cycle. Appeared to have started from a big cornice drop. Initial crown >1m that spread all the way around the entire bowl. A ~35cm stepdown was present after the initial crown. Avalanche ran out down over one bench in the slope and continued all the way down to the lake and smashed a hole in the lake. Bed surface was a hard smooth ice crust.