Human triggered slide

Observation Date: 02/21/2020

Swan slabs, north facing peak to creek ski run from Romney ridge to Blodgett creek.



New Snow:

Avalanche Activity:
We dug a pit at 7,000 feet on a north facing slope with a thin (140 cm) snowpack on Romney ridge during the approach to the Swan slabs. We only tested the snow down to 90 cm, and did not get any propagating results in ECT tests. I ski cut a 20 cm deep soft slab at my feet in the steep (45 degree) and thin/funky entrance to the Swan slabs couloir. The slab propagated about 50 feet across, but since the slab did not extend very far down the slope, it didn’t entrain much snow. I would speculate it ran on a thin layer of facets, perhaps the same one that folks have been finding deeper in the pack around Gash and elsewhere, but I didn’t do a crown profile to further investigate. We felt comfortable skiing the remainder of the steep ski run.

Visual observation showed several old wind slab crowns on steep wind loaded aspects from last week’s storm, predictable roller balls, and some glide cracks opening up. We also heard quite a bit of wet slide activity from across Blodgett in the afternoon, but much of the audible noise was Blodgett falls falling down.

Other Comments:

Observer: Brian Story