Observation: NWAC Forecaster

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Weather Summary

Very cold with light E winds below ~5000ft, warm and steamy above with moderate W winds. A mix of light freezing drizzle and snow fell throughout the day.

Avalanche Observation Comments:

Remotely triggered one small windslab (D1) SE at 5,900ft. It was ~15cm deep and ran on very low density newer snow.

Snowpack Observations

Found a variety of snow conditions today, and a complex snowpack with three failure layers.

At 4,000ft WSW aspect in a sparsely treed area with no wind, HS was 105cm. Found a thick layer of buried SH down 40cm. This layer failed easily with propagation saw tests (was too soft for CT or ECT). PST 10 and 15/100 (End).
Near the ground (80cm down) there was about 25cm of basal facets in the form of some interesting grains- chained up faceted melt forms. These were 4F- hard. ECTP, 23. Deep Tap Test Moderate with sudden collapse.

Moving higher in the terrain we found a suncrust from 12/18 to be mostly thin and friable, with weak snow sometimes above it, but consistently beneath it. We had one large collapse in a wind loaded area that appeared to occur on this layer. These were ~1mm FC and often 5-8cm thick at 4F-. On S aspect at 5350ft got CTM SC beneath the thin suncrust about 45cm down.

In the low 5,000ft range, Tilt tests would often fail about 5cm above the suncrust on small grained facets.

Once in mid 5,000ft range the W winds were transporting snow at a moderate rate. Strong over weak structure was fairly easy to find with 1F wind slabs over 4F snow above the sun crust. The crust generally felt thicker in these elevations. In thicker drifts on a ridgeline, could be long shooting cracks. One slope slid upon approach, from a distance. See description of the small avalanche above.