Weak layers on snow surface and propagating buried SH

Location: Cement Creek Area
Date of Observation: 02/16/2017
Name: Zach Guy
Subject: Weak layers on snow surface and propagating buried SH
Aspect: North, South West, West, North West
Elevation: 10300 – 12100 ft

Avalanches: A handful of recent wet loose avalanches on steep sunny slopes from the past few days. One full depth glide avalanche and one narrow wet slab avalanche, both on easterly aspects BTL, ran sometime in past couple days. No signs of instability where we traveled except some rollerballs on sunny slopes.
Weather: Light NW winds, clear, warm.
Snowpack: Widespread, well-developed near surface facets (1-1.5mm) and patchy surface hoar layer (2-5mm+) on the surface on all shaded or low angle terrain. At lower elevations, this is above a thin, soft melt-freeze crust, with facets on both sides of the crust. As we gained elevation above 11,000 ft, the snow surface was denser, with some wind texture from recent east winds, and the near surface facets are smaller (less than .5 mm) and less pronounced. These weak layers appeared to be moistening into a crust on steeper, sunnier aspects (SW aspect observed). Dug one pit in a wind sheltered, north facing slope at 10,800 feet. The 1/19 surface hoar layer (3-8mm) showed propagation, moderate initiation, 65 cm deep below a 1F slab. (ECTP19, SC)

Propagating results on surface hoar, buried 2 feet deep below a hard slab.

Narrow D2 wet slab on Gibson Ridge (E, BTL). Ran sometime in past few days.

Full depth glide avalanche. NE aspect BTL.

The stage is set for our next problematic persistent weak layers, in some places surrounding a soft crust.