Quick report
- Cracking
- isolated
- Collapsing
- isolated
I triggered a small collapse involving this layer on a wind loaded W/SW aspect at 8,000', and several collapses on shaded northerly aspects at middle elevations. Some of the later collapses were traveling at least 50 feet, I could see trees shaking and snow being knocked off well ahead of me.
Weather
- Wind Loading
- previous
- Snow Avail For Transport
- small smounts
Sunset weather obs: mild temps and gradually clearing skies. Cloud cover went from overcast to partly cloudy over the course of the tour, with plenty of moonlight poking through by the end. Light, occasionally gusty winds blowing at moderate speeds. Light, frozen precip occurring off and on around sunset.
Snowpack
No formal obs, just moving through terrain and probing and hand pitting. 2/1 weak layer is buried 60-75cm down beneath a relatively soft slab. The bottom 15-20cm of this slab are approaching 4F+/1F- hardness, the upper portion grades from F/F- to 4F. There was sensible iciness present at this interface in all locations I observed it. I triggered a small collapse involving this layer on a wind loaded W/SW aspect at 8,000', and several collapses on shaded northerly aspects at middle elevations. Some of the later collapses were traveling at least 50 feet, I could see trees shaking and snow being knocked off well ahead of me.
Light, frozen precip was falling off and on throughout the tour. It felt like there may have been a very thin rime/drizz/ambient moisture crust forming at the surface at upper elevations, but this may have been present previously (would have been deposited within last 48 hours or so). These subtle crusts seem to form with some frequency in middle/upper elevation terrain around Copper. The snow surface at the highway level was dry at the start and end of my tour.
Mild temps are promoting slab consolidation in the snow above 2/1, and producing some silky smooth ski conditions. Ski pen 15-20cm. Lots of older wind effect up high (from 2/15 time period), but most wind features were soft and pleasant to ski through.
Avalanche
I observed a handful of D1 storm slabs that released on >40 degree slopes during the previous major loading event on 2/14-2/15. I did not observe other recent activity, but the light and visibility were poor for most of my tour.