Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
March 16, 2022
Submitted:
March 16, 2022
Observer:
NWAC Forecaster - Andy Harrington
Zone or Region:
West South
Location:
Bullion Basin

Signs of Unstable Snow

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

Media/Attachments

Isolated cracking in wind-drifted snow.
The Early March Crust. You'll know it when you get to it.
Fresh cornices and smooth pillow-like piles of snow indicate wind-loading.
The snow on sunny slopes got warm and sticky while shadier slopes stayed cold and dry.
https://www.youtube.com/watch?v=Qljkiz-LZQI

Advanced Information

Weather Summary

New/Recent Snowfall:
The storm delivered about 15" of new snow (HST)

Mostly sunny morning and minimal wind. I was out of the field around noon.

Snowpack Observations

The sunshine took a while but was able to warm sunny slopes and get the snow noticeably heavier. I did not notice any wet avalanches by the time I left the field but would not be surprised if there were some given another hour or warming. Near ridgelines, obvious signs of wind-loading were present with textured surfaces, wind-stiffened snow, and freshly built cornices.

The real story was finding the 3/8 facets preserved on northerly slopes. Digging around just below 6000' on a NE aspect, I found 15" (40cm) HST over a 1cm thin crust. Below this crust sat our layer of concern, A layer of weak facets that are 1-2mm in size are sitting atop the Early March Crust. All of the tests performed on this layer failed easily with sudden and planar results. Shovel shear test, compression test, extended column test, and propagation saw test all gave alarming test results.

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