Ruby Range Snowpack Structure

CB Avalanche Center 2015-16 Observations

Location: Kebler Pass Area
Date of Observation: 11/21/2015
Name: Zach Guy
Subject: Ruby Range Snowpack Structure
Aspect: South East, South
Elevation: 11,000 – 12,600 ft.

Avalanches: None
Weather: Clear, light to moderate WNW ridgetop winds. No snow transport
Snowpack: On S and SSE aspects above treeline: Snow surface remained dry. The 11/16 interface is a stout meltfreeze crust, 2-4cm thick, pencil hardness, across all terrain. Below the 11/16 crust is a 1.5mm fist hard facet layer, generally around 5cm thick. In some cases, there is another crust layer at the base. There is anywhere from 10 to 70 cm of recent, settled or drifted snow above the 11/16 crust. F to 4F in hardness, except in heavily drifted spots where it is 1F. In one pit location, we observed 1mm near surface facets above the 11/16 crust, and stability tests showed propagating results on this layer (ECTP12x2, Q1, 30cm deep). See video. We got a soft collapse near this pit location. A second pit location did not have these surface facets above the crust, and the recent snow appeared well-bonded. Stability tests showed sudden collapse results below the 11/16 crust in the facet layer. This crust was thick and strong enough that we did not get any collapses on it.