Quick report
- Red Flags
- Recent Avalanches, Heavy Snowfall, Poor Snowpack Structure
Today I was in both upper Moffit Creek and on Shingle Mill Flat. On Shingle Mill Flat, I remotely triggered this avalanche which was confirmation of how dangerous northerly aspects are.
Northerly aspects are easy because they are simple dangerous and more avalanches are likely.
It's the other aspects that we've been spending more time assessing. Today I dug on a southeast facing slope and a west facing slope. Of note, in both of my pits I got an ECTP22 (it took 22 taps for the weak layer to collapse and propagate a crack across the column). JG got the exact same score on a NW facing slope at 10,000 ft somewhere in upper Weber Canyon
Below is a profile and photos from the West facing slope at 9150'. At a similar aspect and elevation, I saw a slope where a moose had triggered a collapse/crack and released a tiny piece of snow. Notice the crack above the slope under the moose tracks and the small piece of slab that released.
Below is a photo of a pit I dug on a southeast facing slope at 8700 ft.
Coverage is unbelievable. South aspects have so much snow.
First photo shows how much the new snow has settled (or compressed) by the settlement cones around the saplings.
Second photo shows how much new snow there is.
Third photo shows evidence of some northerly winds last night.
Snowpack
- Instability Comment
- <p>Big picture - it's pretty simple. There is a buried weak layer that exist on nearly all slopes. Recent snowfall has added weight and stress to the layer. Many upper elevation north facing slopes have a hard slab of wind blown snow on top of this weak layer. Also, this layer has been reactive even at low elevations.</p> <p> </p> <p>Small picture - it's a bit complicated. This layer has generally not been reactive on more southerly aspects but we don't trust it yet. On many mid elevation southerly aspects, the weak layer has an ice crust on top. At lower elevations, this layer is mixed in with the bushes and rocks, but some slopes have a smooth ground surface while others are more bushy and rocky.</p> <p> </p> <p>Bottom line - Keeping the big picture in mind is my approach, and I'm not ready to step out into avalanche terrain.</p>
12-20 inches of very light new snow. Despite the buried weak layer, the snow just above it and below it is vey hard and supportable. There's tons of traction and riding through the powder is very easy.