Observation: Public
Observation Details
Name:
Nate Hough-Snee, Evan Honeyfield, Andrew BreibartObservation Date:
February 21, 2022Submitted:
February 28, 2022Zone or Region:
East CentralActivity:
Skiing/SnowboardingLocation:
Entiat/CopperObserved Avalanches
Did you observe any avalanches?
YesAvalanche Type:
Dry Loose (Sluff)Size:
Size 2: Could bury, injure, or kill a personElevation:
6000'-9000'Aspect:
NComments:
Noted dozens of recent dry loose avalanches in steep terrain from the 19-20 February storm above the Copper drainage and the Entiat headwaters. Avalanches seemed isolated to steep features and were largely L-N-R2-D2 running 200' to 1000'. Notably, none of these stepped down to deeper layers below the Valentine's crust, indicating the February high pressure had created a strong bed surface.Signs of Unstable Snow
Did you see shooting cracks?
NoDid you experience collapsing or whumpfing?
Yes, IsolatedObservations
(Composite ob from several days 18-22 Feb) A day after the 19-20 Feb storm, at 5500' on north we noted CT results that failed on facets below the Valentine's crust (14 Feb) with 10-12 taps and resistant or sudden planar shears. In some cases, multiple crust-facet layers failed on the same tap. While these results on isolated columns were clean, the larger crust seemed to bridge under a skier's weight up until about 7000', where 14 Feb crust became thinner and the likelihood of a cornice, wind slab, or skier triggering slab avalanches became more likely. HST ranged from 6-10cm at 4000' to 40cm at 7000' where winds had created soft drifts and scoured some areas to crust from the February high pressure.
Another major note is that crevasses were out with large cracks below Fernow and Copper, even after the 19-20 Feb storm. By 22 February, the storm had settled out nicely and skiing had improved dramatically over the 14 Feb crust.
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