Large avalanche on east facing aspect

From woody ridge, we observed a large avalanche across the republic creek drainage (not sure what the peak is called but see the coordinates). I heard it first since it sounded like thunder or a plane, and then saw a huge cloud of snow moving down the mountain across the drainage.  We do not know if it was natural or triggered by someone.

We also observed large collapsing and whumpfing at the top of woody ridge on wind loaded slopes. Nothing moved as it was less than 30 degrees.