Observation: NWAC Forecaster

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Weather Summary

It was snowing lightly at the trailhead in the morning, mostly S-1 during the day, with brief periods of S1. Winds were light, with occasionally moderate gusts. Previous wind drifting was evident with up to 15cm drifts in places. I did not observe any actively blowing snow at the ridgeline. Precipitation had changed to rain below 4500ft by the time I returned to the trailhead.

Snowpack Observations

The snowpack near and below 4000ft is very thin, and some steep southern aspects are just bare ground.

At all elevations, there was 5-10cm of new snow. Below the new snow was moist, slightly harder snow that had not refrozen. I found surface hoar at this interface, although it was mixed with other crystal types, and you had to look hard to find it. While there wasn't much new snow for avalanche concerns, this interface was weak and would fail on isolation in hand pits.

A snow profile at 5600ft on a north aspect showed a thin, layered snowpack. The pack is moist throughout, with drain channels present. The new/old interface is 5cm down from the surface, with surface hoar, near surface facets, and precipitation particles mixed together. I could not discern the Valentine's crust from the MLK crust in this location. Blewett Pass received much less snow during that time, and these crusts may present as one crust at these elevations. The MLK crust is down 30cm, the 1/4 surface hoar is down 60cm, and the Christmas crust is down 75cm. Weak faceted snow surrounding these crusts shows signs of strengthening and is now 1F to pencil hardness. An extended column test yielded no results. Basal facets are still present, 4-5mm, but have some rounded edges and sintering (P hard).

I found some areas with small pockets of wind-drifted snow up to 15cm deep. I observed no cracking within the wind-drifted snow, and test slopes did not produce any results.