Improving basal weak layers and newly forming surface weak layers

CBACCBAC Observations

Date of Observation: 01/19/2022
Name: Eric Murrow Zach Kinler

Zone: Northwest Mountains
Route Description: Snowmobile out Kebler Pass to Cliff Creek trail. Skinned around from 10,200 – 10,900 feet on East Beckwith.

Observed avalanche activity: Yes
Avalanches: Took a closer look at a previously reported avalanche on East Beckwith. This avalanche likely failed around 12/31, was D4 in size and ran approximately 1.25 miles from crown to toe of debris. It trimmed mature trees along the edge of its deposition zone and terminus. Another impressive avalanche from the Holiday natural cycle. See photos and estimated path in Google Earth image.
Weather: Thin high cloud cover to mostly clear skies. Generally light winds below treeline and moderate temperatures.
Snowpack: Near Horse Ranch Park at 8,900 feet the snow depth was 115cm and increased to nearly 250cm at 10,900 on East Beckwith. Basal weak layers in a northeast-facing test profile site at 10,500 feet were 4f+ to 1f- in hand hardness, rounding, and 2-4mm in size. The slab at this semi-sheltered site was around 2 meters thick or slightly more. Facets .5mm (a bit larger but generally below 1mm) were present on protected northerly terrain. An east-facing slope at 10,800 feet had a 1cm melt/freeze crust at the surface with small facets below. A due south slope at 10,800 feet had wet snow at the surface 5cm thick.