Observation: Turnagain

Mostly clear skies in the morning and cold temperatures at the parking lot. Clouds moved in from the south around noon and the visibility shifted to overcast. Calm winds at all elevations.

1-3 mm surface hoar on top of about 4-5" of settled new snow. Some wind effect on prominent features but mostly the surface snow was still soft.

We dug two sets of snowpits. One at 1800' on the NW shoulder of Cornbiscuit and another on the lower portion of PMS bowl at 3150' on a SW aspect.

In the lower elevation pit we found the 1/25 melt freeze crust with a layer of facets on top buried about 20 cm (8") deep. The layer did not propagate in our stability tests but it might be more reactive if it had a stronger slab on top, like in areas that are wind loaded or received more new snow recently. The 1/10 surface hoar layer was buried 50 cm (20") and had propagation in two extended column tests (ECT P 24, 25) in the lower elevation pit. The layer of surface hoar had very large crystals in this location and they were well preserved in the snowpack. It is worth noting that another pit just a few meters away did not have propagation on this layer.

At 3200' on a SW aspect the top 40 cm (16") of the snowpack was made up of alternating soft snow and old thin wind slabs. There was a layer of facets down 40 cm which collapsed and had partial propagation in an ECT (ECT N 17). The 1/10 buried surface hoar was down 80 cm at the upper elevation pit and had no results in our ECT (ECT X). It did fail in a propagation saw test but with a pretty long cut length (PST 47/100 end). This layer seemed much less concerning in the upper elevation pit.