Valanga

Avalanche: Ant Knolls

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Avalanche

Slab Width
305 m
Weak Layer
Facets
Trigger Type
Snowmobiler
Avalanche Type
Soft Slab
Slab Thickness
61 cm
Trigger Detail
Remotely Triggered
Start Zone Aspect
East
Avalanche Problem
Wind Slab
Start Zone Elevation
2865 m

Triggered from about 50 feet away. Screen shot of the topo map shows the approx location of the slide (red line) and approx location of trigger point (blue dot). Runout angle of north lobe of debris was 21°

Forecaster Comments:

This is a significant avalanche that failed on a thin 2cm layer (4F) of facets that formed last weekend and buried Tuesday night with the storm(s). It was very difficult to tease out the weakness in terrain adjacent to the flank and snow tests did not yield any hints or clues. Later - and higher - at the fracture line, it took some effort to tease out the weakness. All ECTXs and certainly no cracking or collapsing. (You know how we talk about weak sugary facets? This was not that.) This 2' deep and 700' wide soft slab avalanche was the only avalanche I saw from the Snake Creek trailhead and past the Ant Knolls.

Hardesty