Northwest Avalanche Center

Observation: NWAC Observer

All Observations

Basic Information

Observation Details

Observation Date:
December 26, 2021
Submitted:
December 26, 2021
Observer:
NWAC Observer - Drew Lovell
Zone or Region:
East North
Location:
Hwy 20 (SE thru SW, 3000'-6700')

Signs of Unstable Snow

Recent Avalanches? 
None Observed
Cracking? 
None Experienced
Collapsing? 
None Experienced

Media/Attachments

The Solstice Crust was down 50cm in a test pit on a south aspect at 5100' on Delancey Ridge
Deep trail breaking from lots of recent snow. Periods of light snowfall yielded to weak, filtered sunshine w mostly overcast skies. Washington Pass

Advanced Information

Weather Summary

Cloud Cover:
Overcast
Temperature:
2°F
Wind:
Calm
New/Recent Snowfall:
10cm HN overlies 50-60cm settling snowfall from the week. Ongoing snowfall seems to be almost outpaced by settlement.

Cold and calm. Periods of light snow yielded to weak, filtered sunshine and predominant overcast. (see photo) The upper 50cm of the snowpack could easily be available for transport.
In contrast, the valley floor near Mazama was heavily affected by the ongoing down-valley winds, presumably channeled by the Methow and Lost watersheds from the Fraser River outflow event.

No avalanches observed

Snowpack Observations

Snowdepths on southerly slopes on the far eastern portion of Delancey Ridge ranged from 110cm to 180cm.

The Solstice Crust was down 50cm in a test pit on a south aspect at 5100'. (see photo) Compression Tests produced no results and it was well-bonded to overlying recent accumulations. The crust is 1cm thick and 1F+ in hardness and seems to be decomposing.
We ski tested steep, unsupported features. Although we could generate some loose dry activity, it failed to entrain down to the crust.
Nonetheless, it is probably worth keeping the existence of the Solstice Crust in mind (easily discerned with a pole plant, but not felt while skiing) moving forward, with the inevitable faceting of the upper snowpack, and possible implications for a future loading event.

The Early December Crust was down 140cm above 6000'.

We found no other layers of note today, and windslab was absent in terrain observed.

Favorable hardness profile, but what is the true hardness of cold smoke?

Avalanche Problems

We found no problems today, other than minimal loose dry activity. We expect that this problem will become a bit more of a concern as snow surfaces lose cohesion with the cold air temps. this week.

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