Location: Brush Creek Area
Date of Observation: 12/03/2018
Name: Eric Murrow
Subject: West Brush Creek from Monday 12/3
Aspect: North East, East, South East
Elevation: 9,000′ – 11,000′
Surprisingly only ID’d one slab through this terrain. Very small D1 tucked immediately below ridge top on NE aspect.
Weather: Cold day with mostly cloudy skies and light flurries. No accumulation. Winds were mellow at below treeline locations. Did not observer transport across higher terrain.
Snowpack: HS ranged from around 40 to 75 cm across terrain and variety of aspects. While walking through low angle meadows we were able to produce numerous collapses below Thanksgiving slab. A few of these collapses ran around 75′. The goal for this day was to identify if Persistent Slab structure existed in this shallower part of the forecast area. SE and S aspects below treeline were bare ground prior to Thanksgiving storm – structure consisted of 20cm 1F hard Thanksgiving slab on ground, 2 to 3cm melt/freeze crust capping Thanksgiving snow, top 25cm from the storm this past weekend. No real issues S and SE below treeline.
East and northeast were a different story. Much of this terrain showed thick melt/freeze crust at the ground from October snow, 15cm of 2-3mm facets from early November, 20-25cm 1F Thanksgiving slab, topped with 25cm low-density snow from last weekends storm. Structure out west Brush Creek on shady slopes mirrored areas in Kebler and Paradise Divide below treeline but snow totals were shallower and Thanksgiving slab is only 6″ – 10″ thick. The real concern in this area is collapsing below the Thanksgiving slab. The profile included below is for one such site. We were able to produce propagating results on NE @ 11,000′. Slabs are just thick enough and hard enough that avalanches are possible. We did not get up to the drifted near treeline terrain in this area, but looking through binoculars made leeward start zones look much deeper than below treeline.