Date: 12.31.17
 Location:  Profile lake basin Zone/Region:  Sawtooth Mountains
 Activity:   Ski Toruing
 Marked with checkmark if observed:
  Cracking (widespread)  Collapsing (isolated)  
 Comments: We toured from the Stanley ranger station to the bottom of the first headwall on the way up to Thompson peak. We observed constant shooting cracks coming out from our skis and we observed collapsing associated with whumpfing 4 times. Whumpfing was once around the 7000 foot level in the trees and 3 times between the 7500 and 8000 foot level. At 7800 feet just above first lake on a SSE aspect we dug a pit and performed an extended column test. In the area of our pit we had clear skis and no wind nor any evidence of wind loading. The snowpack was 110 cm deep. From 110-95cm the snow was 4 finger hardness. From 95 to 65cm depth the snow was 2 finger hardness. From 65cm to 50cm we observed a fist harness facet layer. The remainder of the snowpack was single finger or knife hardness. We preformed an extended column test on a 30X90cm isolated block. After 10 wrist and 10 elbow hits we had a fully propagated failure on the facet layer between 65 and 50cm depth. We also noticed a failure at the 15cm depth on a thin facet layer that we think failed at the same time as the deeper layer. We did not notice the thin facet layer prior to the failure. The whumpfing and shooting cracks and pit spooked us enough to turn around before heading onto slopes steeper than 30 degrees above the first lake. We ran into Ben on the way out.

Upper failure on thin weak layer

Lower failure on thick facet layer

Pit hardness profile

The SICKle