Snowpack

Clear Ck - Bald Mtn out of bounds terrain

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Quick report

Visit to the site of a remotely triggered slide in the out of bounds terrain on Bald Mountain (Sunrise expansion area, Clear Creek drainage). This slide failed on a mid-pack crust + facet layer that formed in February. 

Avalanches observed were via glassing with binoculars. Will post photos and info in a separate observation.

Weather

Air Temp
teens
Cloud Cover
clear
Wind Loading
previous
Recent Snowfall
40cm past 36 hrs
Snow Avail For Transport
moderate amounts

Snowpack

Wind effects: The crown from Sunday was 4-8 feet tall in places and was blown in for the most part (no gelande jump getting off the crown). The wind-transported snow from the past 36 hrs was a widespread 5-10cm thick wind skin in exposed middle elevation terrain, and 1-2 foot drifts at and just below ridgelines/crossloaded features. The thicker drifts did not crack and did not behave like slabs where we traveled. 

Sun effects: SE-S got moist by 2 PM, but not enough to cause wet loose issues by the time I left. The post 2/25 storm snow had settled to about 20cm of mashed potatoes on sheltered middle elevation solars. 

Surfaces: Mixture of sun crusts, near surface FC, and radiation recrystalization forming today on S-SE-E-NE at middle elevations.  

Crown/failure layer: Determining what this avalanche failed on was difficult due to 1) 30-50cm of snowfall since the avalanche, with loading winds    2) significant snowpack/structure changes with subtle changes in aspect along the crown   3) signicant snowpack variability (depth and structure) due to variable wind-loading all season along the crown. The slide failed on small facets above a thin crust, located 40-70cm above the ground. The slide did not fail on 1/6; this layer was easily observable deep in the snowpack. My best guess is the 2/14-16-18 or 2/25 crust+FC layers, but I can't completely rule out 2/1 as the failure layer.