| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | No |
| Cracking (Shooting cracks)? | No |
Observation: Turnagain
Location: Tincan Common
Tincan Common (3200′) via backdoor route
Obvious signs of instability
Observer Comments
Debris from a day+ old small avalanche on a SE aspect, 2700', just above treeline was covered by a few inches of snow - see photo below. A similar small debris pile was under a steep roll below hippy bowl. Visibility was in and out and light wasn't great for looking across valley... but no other recent activity observed.
Weather
Warm! 35f at the parking lot by mid-afternoon, and in the 20s/low 30s along the entire route. Overcast to obscured skies with valley fog - just above road elevation - moving in and out. Short periods of moderate snowfall in common bowl with no real accumulation. Winds generally variable and light below treeline, but for a few short periods moderate NE winds above treeline.
Snow surface
Fairly dense snow from the past week even above treeline, with a moist surface below 1100' by mid-afternoon. Ski penetration of 8-12" below treeline, decreasing to 2-6" above treeline. A breakable melt freeze crust was present from the parking lot to 1200'.
Snowpack
Winds during the past week redistributed the new snow above treeline, but the surface always had 2"+ of softer, dense new snow. Probing from 3100' to 3200' on the standard up-track found the New Years crust to be generally 50 - 80cm from the surface, with rare outliers ranging from 10cm to 120cm from the surface. The variation in the NY crust hardness and structure as previously reported was apparent during probing; occasionally the probe would have to be forced through the crust, and other times you could almost miss a series of thin crusts.
See snow pit results below: 3200', SW aspect, HS=235cm and 30 degree slope. Pit location was just east of the standard up-track, ~50' below ridgeline, and the NY crust was 60cm from the surface... making this a slightly thinner location. CT 16, 26 SC and ECTX down 55cm within a layer of fist+ .5mm rounding facets. The failure was in the middle of this facet layer, which was ~5cm thick over the NY crust. While the ECT didn't fail during the standard tests, it did fail and propagate with a resistant planar character on the fourth 'overdrive' hit, breaking 2-3cm higher than the compression tests, at the interface of the rounding facets and the 1/10 new snow.
Finally, from the parking lot to 1500' a thin easily breakable crust was present 16" below the surface. This crust had the appearance of a clear rain crust up to 1200', and from 1200' to 1500' it was a slightly thicker - up to 1cm - and a melt freeze crust.
Pit results/structure referenced above
Debris covered by a few inches of new snow at 2700', SW aspect (just above treeline)
Valley fog and overcast skies - trying every so often to break! - but they failed to really do so.
A moment of moderate snowfall and bad visibility just before skiing... oops. Also note how recent winds have cleared snow to the ground just north of Tincan Common ridge; this has occurred in isolated wind exposed locations throughout the pass.