alpine avalanche activity

Observed evidence of large natural avalanche on alpine slopes across the highway from Parkers Ridge at location shown on map (above Nigel Creek). Involved multiple start zones and single narrow runout zone with accumulation of debris to BTL. Appeared to have failed to near ground, possibly on Halloween crust and/or basal facets. Start zone was extreme alpine terrain, inclination is estimated. Slab thickness unknown and is estimated.