Observation Date: 02/16/2021
We rode up Trout Creek to Hoodoo Pass and dug a pit on a N aspect.
Cloudy, temps in the mid 20s. Several inches of new snow since Feb 14. Light snowfall during our ride, about 1/4 inch accumulated on our sleds while we dug our pit.
Winds moderate from the S, with enough snow transport to begin filling in our tracks after a few hours. Lots of evidence that S and W winds had loaded upper portions of slopes near the ridgelines, and we observed winds transporting snow on ridgelines all the way down the canyon on the ride out.
New Snow: 0-3″
On steeper road cuts around 4500 ft, with a N aspect, we observed a few places where tree bombs had set off small slides that had crowns ~3 inches deep, which we estimated was the amount of new snow that had fallen in the past 48 hrs. We interpreted this as evidence that new snow was not well bonded.
Dug a pit on a N aspect at 5800 ft. Observed non-propagating fractures in our ECT, the first about 10 cm down, and the second down 20 cm. To the naked eye, it was unclear what type of weak layer was leading to the failures. We had no other ECT results, but when one of us stepped on to the top of the column, the layer of facets beneath the Jan rain crust failed more than a meter down, propagated, and the block started sliding. A result that supports the difficult to trigger, but serious consequence of our persistent weak layer problem. We tried to replicate the small slides we observed on road cuts by slope cutting small slopes, but could not get any of the new snow to move in wind sheltered areas. Due to obvious wind affected snow near ridgelines and the presence of a persistent weak layer, we stayed in the meadows and out from underneath steeper slopes.
Observer: Daniel Mason