Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 2
On slopes facing the north half of the compass in some areas, people are likely to trigger dangerous slab avalanches failing on a sugary buried persistent weak layer. Although becoming less frequent, observers in the Logan Zone last week reported signs of instability in some areas, including audible collapsing and cracking. This week's warming temperatures could cause increasing instability on slopes plagued by this buried persistent weak layer. The warming will soften existing slabs and crust layers, and increase creep and glide rates, which could cause natural avalanches to become more possible and triggered avalanches more likely.
- In some isolated areas, avalanches still might be triggered remotely or from a distance.
Very weak faceted snow is buried and preserved in many areas. Poor snow structure exists where a slab of harder snow sits above these buried layers of loose faceted snow, and in some areas, stability tests show unstable conditions.