Sneaky Wind Slabs

We wore a lot of layers to sled into the Northern Whitefish Range and suss out any wind slabs still sensitive to the weight of a rider.

• On an exposed, northeast-facing test slope at 7,000 feet we got shooting cracks and collapsing in hard, recent wind slabs. We would have triggered a few small avalanches here, but the slope was too small and well supported for the slabs to slide. They tapered from 10 inches thick to 5 inches thick about 20 feet down slope. Every other wind feature and cornice we found barely cracked, so the problem seemed to be isolated to a few favored slopes at upper elevations.
• We found the majority of wind-drifted snow on north through east-facing slopes (from southwesterly winds) though we did find some cornices and hard slabs on southwest-facing terrain from recent northeast winds. The wind-affected snow was sneaky because all of the surrounding trees still had snow in them and because the surface was covered with a few inches of soft snow that masked the wind-affect.
• We dug two snow pits and found an eggshell crust with faceting snow above and below it. We found this structure at all elevations we traveled. We got no propagating test results around the crust. The cold temperatures seem to be allowing for some faceting in the upper layers of the snowpack. We did get a few results in one pit on the layer of rounding facets above the deeply buried basal crust.
• My partner today was an avalanche course instructure who had just taught a Level 1 course in a nearby drainage. His class found widespread, small surface hoar on east-facing slopes above 6,600 feet on Wednesday the 29th. They found a layer of buried surface hoar on the same slopes down about 50 cm. The buried layer was getting crushed by the overlying snow and was unreacitve to their tests. We did not find any surface hoar (buried or otherwise) on our travels today, which means that it may be sportty.
• The upper snowpack seems to have settled a bit, and we saw small settlement cones around the trees. When we skied steep, sheltered terrain back to our sleds we got no sluffing.