Public Observation

Observation Details

Observations

Today was a bluebird day in the Sierra. Several hundred feet from the ridge line of the gully I was in, the wind picked up dramatically from the north/northeast. I noticed some wind slab formation in certain exposed areas of about a depth of 15cm with no instability noted and I did not see very much wind transport happening in front of me. A quick hand pit revealed faceting crystals underneath this layer. I chose to dig a more proper pit in the shade below a tree at 10,789 feet to see a little bit more of what was going on this area. It was only 65cm deep but I was surprised to find two thin layers of pencil/knife- hard ice that I did not expect. A compression test showed a collapse at 9 taps above the first ice layer and then a collapse at 12 taps between two softer layers. Everything else to the ground appeared to bond well. No instability was noted anywhere on the ski down in the trees.

Signs of Unstable Snow