Public Field Report

Observation Details

Signs of Unstable Snow

Observations

BLUF: Persistent slab problem still exists on shaded, NE facing slopes at moderate elevations.

We were prepared for wind, cold temperatures, and considerable avalanche risk given the recent large amount of snow fall over the prior base layer. There was no wind but temperatures were below freezing, around 0-5 degrees. The sky was blue and visibility was high. At 2:00pm, our group dug four snow pits in Lower Twin- Left at approximately 8300 feet on 20 degree NE facing slope with snow height of 160cm. There were four layers, the first was above 95cm, the second 95cm -145cm and a third layer from 145cm-160cm. The first layer was lighter snow, second layer was harder, third layer showed crystal facets and the fourth layer was lighter snow. With the compression test, 3 had no fracture (CTN), and one had a very easy fracture (CTV). On propagation saw test, no propagation was seen on the first one and propagation was seen on the second one, about 1/3 of the way (ARR).