Observation: Public

Observation Details

Signs of Unstable Snow

Observations

Today we did two laps on the north aspect of Castle Col. There was a lot of new snow that was mostly right side up expect for the high moisture snow near Narada Falls. We did not see not trigger any avalanches on what seemed to us to be stable snow. Near pinnacle peak there were wind slabs that produced shooting cracks during the uphill portion. A pit was dug on the NW aspect at 5900ft (33deg). Photos below show the hand hardness testing that was done. From a Compression test we observed CTE but with a Q3 shear quality. On the extended column test we observed similar results in our first tapa. However we removed the slightly cracking new snow and continued tapping and had a collapse at tap 13 and a full propagation at tap 15 (ECTN 13). This has a Q2 shear quality and failed on buried surface hoar observed. We measured a snowpack depth of 1.95m and the facets were found at 1.55m. The snow while skiing and skinning felt safe but these results were slightly alarming. Overall a fun day in the tatoosh.