Large natural on west side of Ruby Range

CB Avalanche Center 2015-16 Observations

Location: Kebler Pass Area
Date of Observation: 01/14/2016
Name: Zach Guy
Subject: Large natural on west side of Ruby Range
Aspect: East, South West, West
Elevation: 10,000-11,800 ft

Avalanches: We came across a surprisingly fresh D2.5 debris pile on west side of Ruby Range. Start zone obscured by clouds. Appears to have failed in the past week because the 10″ that fell on 1/7 was not on top of the debris. Could see some flanks mid track that looked about 2 feet deep and gouged to ground. Start zone was either SW or W aspect above treeline. Speculating that it was a persistent slab triggered by either a small wind slab a few days ago or a small wet loose avalanche yesterday? Noteworthy because it is the only persistent slab we’ve seen fail in the past few weeks, and one of the only large naturals from that aspect observed during Xmess Cycle. We observed 4 fresh wet loose avalanches on S/SW aspects below treeline.
Weather: Light to moderate snow (S1-S2). Moderate WSW winds with moderate snow transport at ridgeline. Overcast. Cold temps.
Snowpack: 2″ of new snow by 2 p.m.
N/ATL East aspects: Snow depths ranged from 180 to 250 cm. No wind effect in recent snow (ski pen was shin deep), except some slightly stiffer snow at ridgeline. No signs of instability on steep terrain.
N/ATL West aspects: Variable snow depth and structure; difficult to generalize. Upper start zones were mostly shallow and faceted (<50cm), with some pockets up to 180 cm deep with variable hardness structures. No signs of instability.

Small wet loose below treeline
Debris looking up towards obscured start zone
Looking down at debris.  Broken tree limbs and several meters deep.