Public Observation #2023-1112

Submitted:

March 28, 2023 4:42 PM

Observation Date:

March 25, 2023

Zone or Region:

Central Cascades

Activity:

Snowmobiling/Snowbiking

Location:

Paulina (43.68444, -121.23785)

Did you trigger any avalanches?

Yes

Was it intentional?

Yes

Avalanche Type:

Soft Slab

Size:

D1: Relatively harmless to people

Elevation:

Aspect:

Comments:

Did you see shooting cracks?

Yes

Did you experience collapsing or whumpfing?

Traveling by snowmobile along the rim of the Obsidian Crater (rollercoaster). Considerable conditions with large volume of new snow and continuous snow through the day, so stayed away from wind-loaded areas, slopes >25deg, overhead hazards, and terrain traps. Snow was continuous with temperatures between 10-25 degrees through the day. Test pit dug on a NE-facing slope, 25deg. Depth 240cm, new snow interfaces at 20cm (overnight) and 40cm (storm cycle). 1cm crust with facets at 40cm. Beneath 40cm is consistent, consolidated snow. Compression test fractures on tap 1=20cm resistant planar and tap 12=40cm sudden planar, confirming high-risk conditions.

Triggered a small soft slab avalanche on a test slope, NE facing, 32deg. 40cm crown. Propagated beyond test area.

Observation Details