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Observation: Lambs Canyon

Observation Date
1/29/2016
Observer Name
Brackelsberg
Location Name or Route
Lambs/Box Canyon
Weather
Sky
Scattered
Wind Direction
Southwest
Wind Speed
Moderate
Weather Comments
The wind was calm until around 12:00 when it picked up very quickly as the sky clouded over. A wet snow started around 16:30. Late afternoon rain up to ~6500'.
Snow Characteristics
New Snow Density
Medium
Snow Surface Conditions
Dense Loose
Snow Characteristics Comments

There were some significant wind crusts on any exposed areas and in east facing trees near the ridgeline. The snow in tight trees is still well preserved.

Red Flags
Red Flags
Wind Loading
Poor Snowpack Structure
Red Flags Comments
We didn't ski from the top ridge, but based on the quickly degrading considitions as we climbed towards the ridge I would assume there would be sensitive wind slabs.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Increasing Danger
Problem #1 Comments

The snow that started around 16:30 was wet and heavy so my biggest concern will be the additional wet being added to the sensitive snow pack. Depending on the quantity and density, this could impact just the mid-pack weak layers or potentially the basal facet weak layer.

Avalanche Problem #2
Problem
Wind Drifted Snow
Trend
Increasing Danger
Problem #2 Comments

With the increased winds and new snow the northwest to east aspects could be wind loaded and sensitive on Saturday.

Snow Profile
Aspect
Northwest
Elevation
9,300'
Slope Angle
30°
Comments

I have been out of town for 2 weeks and was curious to see how much the snow pack had changed. Reading the daily report and observations, I was expecting a large change, but I was surprised how big the change was. I put a pit in very close to where I skied 2 weeks ago before leaving. January 15 observation here. The basal faceted layer has significantly compressed (45cm to 35 cm). The layer above the facets that was mixed forms 2 weeks ago was not fully faceted, but had gained strength (4F to 1F). The new snow from the 15th was not started to facet and had gained strength.

I had good results from compression tests but no results from an ECT. After the ECT, I was able to put very little shovel shear pressure on the extended column and break the entire column at the ground (see photo 1)

Photo 2 is the large basal facets.

Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Considerable
Coordinates