We didn't see the slide break, just happend on it. There were other snowmobile tracks across the lake but I didn't see any sign thay the had been on the slope. It is a generally rocky south west facing slope. I don't know the angle. Perhaps rapid warming or new snow on a facated layer from sun exposure. Guessing a depth at the break like of about 2 feet.

While in broadhead meadows a while later maybe noon we heard a what we believe to be a large collapse. Sometimes we have heard avalanche control from the cottonwood or ski resorts up there too, so it can be hard to say for sure. We didn't witness anything else other than the noise.