Observation: Pink Pine

Observation Date
Observer Name
Salt Lake » Little Cottonwood Canyon » White Pine » Pink Pine
Location Name or Route
Pink Pine
Wind Direction
Wind Speed
Weather Comments
High thin cloud most of morning into early afternoon. Temps rebounded and were just below freezing at mid elevation, out of the wind. Extreme wind with intense transport observed on Birthday Chutes/Tri Chutes crossloading starting zones of Birthdays. I think I could actually see the Jet Stream. There was evidence all around of lots of wind scouring at the most exposed locations. Even at mid elevation and down in the drainages wind currents were ripping snow off the trees. No new snow during the day.
Snow Characteristics
New Snow Depth
New Snow Density
Snow Surface Conditions
Wind Crust
Snow Characteristics Comments
In sheltered areas near and below treeline, the storm snow has settled to about a foot in depth. Ski penetration was right through this new snow down to the interface with the old surface. Some wind effected snow was observed along the Pink Pine ridge with large pillowy cornices. Did not visit the alpine terrain today.
Red Flags
Red Flags
Recent Avalanches
Wind Loading
Poor Snowpack Structure
Red Flags Comments
Plenty of evidence out there that the snowpack is adjusting to a new load.
Avalanche Problem #1
Wind Drifted Snow
Increasing Danger
Problem #1 Comments
It would be hard not to put this at the top of the list due to the prolific transport happening today. In many alpine start zones, the snow was cross loading so fast it seems like naturals would be likely. And it is also possible that the wind speeds were so great that the snow either sublimated or was blown so far down slope it wouldn't be where you think it should. More wind in the forecast will keep this problem in our face.
Avalanche Problem #2
Persistent Weak Layer
Increasing Danger
Problem #2 Comments
The poor structure is there. However the overlying slab is still gaining cohesion and seems most likely to propagate where the snow has been influenced by wind loading or warming temps/direct solar input. Our observations, and that of many community members, were that the mid-November dry period produced widespread faceting and surface crust development depending on aspect. In the alpine terrain this problem may be more specific in its distribution, whereas the near and below treeline terrain this could be more widespread. Some evidence of small (D1) avalanches in Pink Pine failing on a combo of 2-3mm buried surface hoar and near surface facets. With more snow and wind and snow and wind forecast for the next several days, it is easy to believe we will have pronounced activity on this layer which was buried on Nov 28.
Snow Profile
Slope Angle
Photo 1 shows a small slide that appeared to be remotely triggered in the last 24 hours. Ski tracks were located to the lookers right of the slide. Upon investigation, the failure plane was the Nov 28 surface hoar/near surface facets.
Depth was 12-18" and numerous echelon cracks were visible radiating from the sides of the crown and flanks.
Photo 2 shows wind transport along Gad Valley White Pine Ridge and Birthday Chutes.
Photo 3 shows wind scouring in Maybird Aprons.
Video 1 is wind transport into the Birthday Chutes and even a major gust at our relatively sheltered mid elevation profile location.
Today's Observed Danger Rating
Tomorrows Estimated Danger Rating