Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 3
The snowpack is complex, with weak, sugary faceted snow from January sitting underneath multiple feet of denser snow. Strong snow over weak snow is a classic setup for avalanches. Obvious red flags like collapsing and cracking may be absent, and you may even get a few sets of tracks on the slope before finding the right trigger spot, often a shallower part of the slab near rocks or bushes. High marking comes to mind as a possible way to trigger this type of large and destructive avalanche.
While not widespread, this problem is impossible to navigate. The only sure way to deal with a persistent weak layer is to avoid it - steep and rocky slopes with shallow snow on the north half of the compass are off limits for now.
The slide on Duchesne Ridge produced SUV-size chunks of debris, which stacked up deep in the runout and in the trees below. Getting caught in a dangerous slide like this could be game over -- Trees turn into baseball bats, and debris chunks are like boulders coming down on you.