Public Observation #2021-512

December 24, 2021 1:38 PM
Observation Date:
December 24, 2021
Zone or Region:
Central Cascades
Tam Rim
Did you trigger any avalanches? 
Was it intentional? 
Avalanche Type:
Soft Slab
D1: Relatively harmless to people
Upper playground; crown depth- 1-2ft; width- 100ft; length; 200ft; slope angle at crown~35
It wasn't intentionally triggered but we were all well aware that there was a good chance something would go.
None reported
Toured up from the Tam Rim huts today and found fairly touchy conditions. On our first run we skied a N facing bowl below tree line and noted no signs of instability(other than significant recent snowfall). From there we went up to what I believe may be called the upper playground(N-E facing aspect shortly before the actual viewpoint). We noted that there was wind slab growth on the east facing aspect but we didn't see any shooting cracks and small test slopes didn't seem to be very reactive. Our first skier made a ski cut exiting to the right into lower angled terrain and triggered a substantial wind slab avalanche. It was approximately 100 ft wide and ran probably 200-250 ft. The crown seemed to vary between 1-2ft deep and entrained most of the new snow down to the rain crust. The rest of us just skied the bed surface down. The next run we skied further down(below tree line N aspect) had a steep convexity at the top and a ski cut on this produced a small storm slab avalanche that was ~50 ft wide and ~12in deep.