Observation Date: 11/16/2019

Climbed and skied NW facing chute from Lower Rumble Lake to W ridge of S Holland Pk (8750′).

Cloud ceiling 8000-9000′ throughout the day over both Swan Range and E Missions. No precipitation. Upper elevation temperatures in the 20s. At or above freezing in the mid elevations.

Light winds at the mid elevations, and moderate winds (especially on exposed terrain) at the upper elevations. No snow transport up to 8750′: the snow was moist and had already been wind packed to varying degrees. Lee catchment areas show obvious signs of wind loading.

New Snow: 0-3″

Avalanche Activity:
Isolated and very small (D1) human triggered wind slab (1F) on very steep, lee terrain at ~8100′, NW aspect. Failed on facets at crust.

Other Comments:
Hiking required to about 6900′ before transition to skis. Significant spatial variability of snowpack depth: very exposed windward terrain remains bare, less exposed windward terrain is dust on crust with generally less than 24cm HS, lee terrain varies in depth up to 1.5m (surface conditions vary: pow, supportable windboard, breakable windboard).

Observer: Mat Brunton