Duck Pass - Stability, mid-elevation mid-pack facets

Submission Info
Sunday, January 21, 2018 - 2:00pm
Red Flags: 
37° 33' 32.1048" N, 118° 57' 47.6784" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up to Duck Pass from Tamarack.  COLD morning!  10deg F at trailhead at 8:30am (8,600').  But sunshine was out fully, mostly calm winds except for some very light gusts at ridgetop, beautiful day.  Up to ~12cm (~5") of light density new snow form the past few days in shetered locations above 10,000'.  No new windslabs of note found on any aspects anywhere.  Handpits testing old windboard areas (or windboard under a few inches of fluff) resulted in failures only with very hard force, Q2 shears inconsistently either right under P+ hard windslab, or down a few inches in softer snow.       

No signs of instability anywhere along this tour.  Decent amount of small (D .5-1) dry point releases coming from cliffs along the crest that looked to occur toward the end of the more intense part of this past Thursday's storm.  No signs of rollerballs on sunny southerly aspects.     

Test pit dug at 9900' on sheltered NE facing slope however did show old facets mid-pack (50cm down) to be more reactive than before this cold snap.  See attached profile.  ECT tests propagated with Q1 shear quality (ECTP21-Q2).  This ~13cm thick weak facet layer was found just under the melt freeze crust which the Jan 8th storm snow fell ontop of.  The temperature gradient in this area of the snowpack was found to be 1-1.5deg C per 10cm, which is great enough to continue facet growth, as opposed to before this last storm where very warm air temps and cloudy skies resulted in a weaker temperature gradient which tended these facets towards rounding.  This layer is worth continued observation.  At this time I still don't expect any avalanche activity on this layer either until a substantial new snow load stresses it, or until continued prolonged cold temperatures results in futher faceting to the point that test slopes begin to show failure.  

Snow quality in sheltered trees was great, despite only being being 3-5" of new.  In more alpine terrain exposed terrain: lots of variability from firm windboard, to a few inches of light snow ontop of firm windboard (dust on crust-ish), to patches of softer textured snow.  

Snowpit or crown profile photo or graph: 
Weather Observations
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