| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | No |
| Cracking (Shooting cracks)? | No |
Observation: Turnagain
Location: Tincan Common
Standard uptick to Tincan Common (3300′)
Obvious signs of instability
Observer Comments
Small slab and loose snow avalanches below small corniced ridge w/ active wind transport on lower CFR ridge (see photo below). This activity looked like it only involved a few inches of surface snow.
Runout for a small avalanche observed across valley within a cross loaded feature on Seattle Ridge; we couldn't see the start zone, but this appeared to be natural activity.
Moderate snow transport - with short periods of intense - throughout the day on high neighboring peaks and ridge lines. This included periods of growth for the very impressive Hippy Bowl cornice! Light w/ occasional moderate periods of snow transport on ridges just above treeline.
Weather
Warm with periods of light snow. Snow/rain line was 800' at 10 AM and 4:30 PM.
Surprising broken skies in the AM! .... transitioning to obscured in the early afternoon.
Below treeline, variable light winds throughout the day, coming from the North, East, and occasionally South.
Above treeline, light North to East winds with occasional moderate gusts on the Tincan Common high point.
Snow surface
Wind affected, dense surface snow above 2000' in non-treed areas. Ski penetration of 6" at the parking lot, decreasing with elevation to 1-4" above treeline. The surface snow was denser by the end of the day, with a moist snow surface below 1200'
Snowpack
As pictured below, Tincan common bowl clearly got wind overnight, with nearly all ski tracks covered up from days prior. By the late afternoon most of Common Bowl had been skied, with no apparent avalanche activity.
While the winds changed surface conditions, slabs weren't firm today along the route, with fist+ to four finger snow being common for the top layer of snow in wind affected locations. Hand shear tests where snow had seen wind affect would fail with moderate force about 10-14" from the surface, but with an uneven, non-planar break.
See below for pit results and structure in Hippy Bowl, dug about 100' below ridgeline. Probing from 3100' to the pit location generally found height of snow from 280cm to deeper than my 320cm probe, with some occasional shallow areas. The New Years Crust was generally 120 - 150cm from the surface; pit location was chosen as it was 95cm from the surface.
Small natural avalanche activity from today below CFR ridge
Generally light snow transport along ridge lines near treeline... with moments of moderate transport, like pictured here.
The cornice above Hippy Bowl was getting some attention from the winds today!
Pit results. Of note, the decomposing snow around the 1/25 crust still - just barely - has precipitation particle forms that are still recognizable. This layer is still noticeably softer than snow above and below it, and while bonds are forming between grains, some sharp corners were also evident under the scope. Overall, this layer was less reactive than seen earlier in the week, with an ECTX and one CTN result for the pit... and an ECTN failure (just below the shovel) after extensive overdrive taps!
Common Bowl in the AM, with just a few tracks mid slope still visible from days prior.
Another view of the wind affect at treeline, looking at Common Bowl.
Blue skies over Tincan in the AM, even as mountains to the north and south were in the clouds! ...
... until the afternoon, when we joined the cloud party as well.