Northwest Avalanche Center - Public Observation

Name:

Matt Primomo

Observation Date:

February 3, 2021

Submitted:

February 3, 2021

Zone or Region:

Stevens Pass

Activity:

Skiing/Snowboarding

Location:

Lichtenberg

Did you observe any avalanches?

Yes

Comments:

Wet loose slides ran with strong sun by mid-day on steep solars. Many of these pulled out the 12" or so of recent snow down to the 1/13 crust. One was perhaps a small D2.

Photo:

Strong sun, light wind, no snow transport observed. Previous snow transport with 4F+ drifts to 2ft deep in places.

Profiles all the way up the S side of Lichtenberg revealed fair to poor bonding of recent storms on the stout 1/13 melt freeze crust. The crust is slick and smooth on these solar aspects. Sometimes small rounding facets were observed, other times large, preserved stellars. Sometimes it was a thin crust/facet sandwich.

In any case, tilt tests and compression tests revealed weaknesses about 12-15" down just above this crust. Propagation saw tests showed a propensity to propagate. Shooting cracks could be observed on steep features, and we had one whumph within a thick wind drift at 5,600ft, weak snow over the crust.

The deets:
S at 4,600ft: Planer tilt tests and CTE SP results 30cm down, on a slick 1/13 crust. Some faceted grains observed but mostly preserved stellar.

S at 5,000ft on Lichtenberg Shoulder: Tilt tests easy, down 15cm below recent suncrust. CTM SP down 37cm in 1mm FCxr within 1/15- 1/13 sandwich. PST 30/100 (End) here.

N at 5,600ft: Tilt tests revealed a layer of small buried SH down 15cm.

In general, there was a lack of slab but the sun was 'slabbing up' the snow as we traveled. We stuck to supported features to low 30* and avoided steeper slopes after they had much sun. Going into the next storm there are plenty of potential weak layers to be concerned about.