Quick report
- Cracking
- Observed
- Collapsing
- Observed
I covered lots of ground and observed widespread sun and wind damage at the snow surface. Aside from an uncontrollable fall on these slick surfaces, triggering a hard slab of recently wind-packed snow seemed the most likely way to find trouble currently. Triggered slides would be on the small side, but thanks to the hardness of the slab it would be pretty easy to get magic-carpeted and sent rapidly downslope through unforgiving terrain. The presence of the 12/13 weak layer further down in the snowpack continues to drive the type of terrain that I'm comfortable entering. I experienced cracking and subtle collapsing in the most recently deposited generation of hard slabs of wind-packed snow. Recent avalanches refers to sun-induced wet snow avalanches that likely occurred on 1/15, perhaps continuing on 1/16.
Weather
Beautiful sunny day. N/NW winds blowing at upper elevations at moderate speeds with occasional stronger gusts.
Snowpack
Phew, the central Sawtooth alpine has a lot of rough, rugged, icy, slippery surfaces right now! Northerly winds are never friendly in the Sawtooth, and we have seen a ton of it in the last two weeks...conditions are more reminiscent of what can typically be found in the Boulders and Pioneers. Slopes that directly face the sun have been cooked and blown into icy, difficult-to-edge, slide-for-life crusts with facets below. These are true firnspiegel crusts in many locations. As you move away from direct sun these crusts thin somewhat, become breakable, and are accompanied by facets above and chained facets below. Shaded slopes have been pounded by winds over the past two weeks, generally doing a lot of eroding but also packing some stiff hard slabs into the terrain. The snowpack has undergone an appreciable amount of settling in the last few weeks and there are many open cracks below steep cliff bands that are reminiscent of a bergshrund or randkluft. We are several weeks into the construction of our next weak layer (the current snow surface). It looks like it will be a "productive" weak layer at this point, I expect we will be dealing with persistent slab issues relating to this layer for an extended period. I did not directly look at the 12/13 weak layer, but based on how much activity it produced during major loading events on either side of the New Year and the character of the slides, I will be keeping it on my list for the foreseeable future.
Avalanche
- Size
- D1.5
- Count
- 5
- Aspect
- S
- Trigger
- N
- Elevation
- 9800 ft
In addition to the wet loose activity, I'm also reporting some older avalanches that occurred in terrain that is not easily visible when driving on the highway. I initially observed these slides earlier in the month, before the wind had had its way with things. I suspect I might have seen more avalanches today if the wind hadn't done such a good job of masking their presence. I did not glass for avalanches from my high point due to frigid temps and unrelenting winds, but I suspect I would have been able to find some large debris piles.