Observation: Public

Observation Date:

January 3, 2021

Submitted:

January 3, 2021

Zone or Region:

Snoqualmie Pass

Activity:

Skiing/Snowboarding

Location:

Mt. Catherine

Did you trigger any avalanches?

Yes

Was it intentional?

No

Avalanche Type:

Soft Slab

Size:

Size 1: Relatively harmless to people

Elevation:

4900ft

Aspect:

N

Comments:

Skiers standing still when small slope above released during large gust of wind (dislodged tree bomb?) ~50ft below E end of Mt. Catherine sub-summit ridgeline. Crown varying 3-6in deep, ~50ft wide, ran 20-50ft depending on terrain features. 1 skier knocked over and carried 5ft into tree, buried to knees. No injuries. Bed surface fairly soft and easy to penetrate skinning. Amount of snow entrained likely would have required a terrain trap for full burial. No wind observed aside from described gust and visual indicators of wind transport were absent.

None reported

12"+ heavy new snow in most open areas, continued snowing throughout tour. Saw 1 other oddball crown in photo 3 just below incident location. No other instability noted aside from sluffing storm snow during ski out.

seen on uptrack just below incident location