Avalanche

Avalanche: Beaver Basin

Chris BensonMoab
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Avalanche

Slab Width
762 m
Weak Layer
Facets
Trigger Type
Natural
Vertical Fall
610 m
Avalanche Type
Hard Slab
Slab Thickness
91 cm
Start Zone Aspect
Northeast
Avalanche Problem
Persistent Weak Layer
Start Zone Elevation
3627 m

Went up for a closer look after observing this slide yesterday off the top of Mann's Peak, and boy it was worth it. Size 3 avalanche that occurred some time last week after the significant storm 11/25-11/26/2024. The main aspect that failed consisted of an unsupported, ENE planar slope that had obvious wind loading at the top. Interestingly, the crown wrapped onto SE aspects as well as due North. Couldn't get to close to the north aspect as it had filled back in, however the more accessable SE aspect revealed a dense storm slab sitting on facets from early season snow. Got 2 ECTPVs, but unsure how that would translate to slope-scale stability as the surface has a stout melt-freeze crust and the mid pack is quite dense. It does suggest that if you find the wrong spot though, you can still trigger a large and destructive avalanche.

The measured alpha angle was around 25 degrees. Significant debris piles over 10' deep were observed.