Observation Date
12/29/2013
Observer Name
Cam Mackenzie
Region
Salt Lake » Big Cottonwood Canyon » Willows
Location Name or Route
Willow Heights
Comments
Mission for the day was a facet hunt only Kobernik could appreciate. What would the snowpack look like on a slope that hasn't seen sunlight all season? Although there is a plethora of complex terrain along the ridge-tops that don't see sun for months, my goal for today was to look at a simple slope without the influence of sun or melt freeze crusts to affect vapor movement through the snowpack. Slope chosen was at 9400' roughly 50 vertical feet below the ridge. Trees below but nothing near the pit.
Results were pretty much as expected. Facets throughout the pack with a large but steady temperature gradient. No crusts found. Well developed depth hoar up to 24cm with multiple striations and cups. 4mm depth hoar along ground likely old October snow was 4+mm in size.
Snowpack strength and structure wasn't great. 3 out of 5 lemons: Weak layer in top 100cm, persistent grain type, grain size >1mm.
Snowpack was carrying energy and propagation well across the column. Definitely potential for large avalanches on similar aspects given a trigger.
Comment on Today's/Tomorrows danger rating: Highly aspect dependent. Considerable on northwest through east facing terrain. Low on south facing except if sun is torching!
Video
First ECT resulted in a Q1 sheer after 19 taps. Tried to replicate it for video but had failure on 21 with a much less planar shear quality.
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Coordinates
