Wild avalanche conditions on Schuykill Ridge

Date of Observation: 12/09/2021
Name: Evan Ross and Zach Guy

Zone: Northwest Mountains
Route Description: Schuykill Ridge, traveled mostly on NE aspects to ridgeline at 11,400′.

Observed avalanche activity: Yes
Avalanches: We skier triggered, remotely triggered, or sympathetically triggered numerous soft slab avalanches, D1 to D2 in size, and observed at least one natural. All of these were breaking on the 12/6 facet layer, 30 to 45 cm deep. Most gouged to the ground through loose facets as they descended, or in a few areas, stepped down to the ground through old slab. The most notable slides were: 1) A skier triggered D1 slab in Runaway Ski that sympathetically pulled out a D1.5 in the same path, which then sympathetically pulled out a D2+ in Thanksgiving Bowl. 2) Yogi’s ran naturally to the bench, D2 in size 3) From ridgeline, we remotely triggered a D2 slide in Thanksgiving bowl that looks like it sympathetically pulled out another D2 in Birthday Bowl. From this same location, or shortly after nearby, we also remotely triggered another D2 in Runaway Ski. We measured the debris pile below Thanksgiving Bowl at 2.5 meters deep, and it snapped a few small trees. All slides stopped at the midway bench. We also triggered a handful of smaller slides below the bench in areas that might surprise you because of how bushy it is.
Weather: Light to moderate snowfall throughout the day. Strong southwesterly winds at ridgetop were drifting snow.
Snowpack: 10″ to 15″ of storm snow over the well-described 12/6 facet layer. Extensive shooting cracks on all open slopes that we traveled. Near windloaded ridgeline, slabs were 2 feet thick and we also got a couple of audible collapses there. Ski pen is close to the ground through the soft new snow and faceted old snow; HS is generally about 2 to 3 ft deep.