Sawtooth Avalanche Center

Public Field Report

Observation Details

Observation Date:
December 18, 2021
Submitted:
December 21, 2021
Zone or Region:
Soldier and Wood River Valley Mtns
Activity:
Skiing/Snowboarding
Location:
Soldier One, Soldier Mountains

Signs of Unstable Snow

None reported

Observations

Soldier One NE slope at 8505; Cloudy and very little wind, around 18 degrees.

Cat track hadn't gone up recently since the end of the storm above the ski area. Was pretty calm in the morning which was surprising, 11 degrees in ski area.

Conditions were quite variable on the elevations, especially above 8000' on Soldier one. Thinner patches in place and big drifts nearby as suspected. Below 7500 we found mostly bare dirt/sage brush with 20+ inches on top of it (terrible for snowboarders) unless in a very shaded area (N to NE or creek bottoms, or heavily timber) where the wind or sun hadn't gotten to. Took a short video of the pit we dug at 8505' on Soldier one and sent it. The CT test was mixed (>10 in one area E face same elevation 80 cm depth, 23 in our main pit), while we didn't get a result on the ECT (>30) in our main pit. My suspicion of drifts everywhere on both sides of the ridges, but larger ones on the NW and N ridges was correct and it was starting to form wind slabs on the surface in areas, no significant cracking on surface quite yet. S facing ridges had larger wind drifts as well from early on in the storm (wind switched on Tuesday according to Soldier 2 gauge). Some of the E slopes and S slopes looked to be safer as its rooted on bare dirt but we kept it at 28 degrees for skiing cause we don't trust the areas where we think bare dirt is and old faceted snow lay (very hard to tell in places).

Pit on NE slope at 8505' on Soldier One showed 115 cm of snowpack in semi-protected area. CT failed at 70 cm on thick facet layer. Not well bonded. Ice at 80 cm, and several more layers of facets 2-3 inches thick each, solid ice layer on ground. No result on the ECT test.

Media

Drifted areas above 8700 on Soldier one, showing variable snow pack depth.
CT of 27 failed on old snow layer in this particular pit. Another pit towards E facing failed around CT>10 in 80 cm pit. Mixed results do to variable snow depth.
115 cm pit showing failure on CT
3-5 inch faceted layer varies in places.
No observed propagation on ECT but I believe it's variable on snow depth and wind consolidation, especially at lower elevation and N shaded slopes.
Close up of facets at 70 cm.