We were traversing the ridge between Two Dogs and Upper Days to Flagstaff, with moderate W wind and heavy snowfall. We intentionally kicked off a small cornice on the lowest angle part of the slope to see what would happen. It propagated much bigger than we expected, and ran fast. There was a 15" crown, and it propagated at least 75' to the either side, maybe further, but we couldn't see any further. The starting zone was over 30 degrees, but it ran faster and further than expected, well down on the slightly lower angle slope below, then out of sight. The bed surface was at the new snow, old snow interface, and it looked clean, but we couldn't get close enought to examine it better. We knew it was wind loaded, but there was no slab, so we expected maybe a bit of a sluff, but not more. It went big enough to turn us around. Sorry no photo-too snowy and windy.