Storm slab and old crust in Cooke

Found 5-8” of fresh low-medium density snow. Triggered multiple small soft storm slabs/sluff which occurred on steeper slopes (40+ degrees). 
also noted an interesting crust overlaying a weaker layer that the new snow sat on. This crust wasn’t found everywhere, but just on the sides of rolls facing west or north west (between 9000’-9400’). When probed with a pole it sounded hollow. The crust was thick in nearly every place we found it and didn’t ever collapse under us, but it did shear in hand pits. A thin layer of graupel was also on top of this crust in some areas. 
other areas where this crust didn’t exist seemed to either not have refrozen completely before getting snowed on, or never got above freezing in the first place (high elevation north facing). In some areas the new snow bonded very well, in other areas it was easier to get it to sluff off the old crust. Attached is a quick photo of the crust location and the weak snow below it.