Persistent Slabs
- Alta quota
- Limite del bosco
- Sotto il limite del bosco
- Probabilità
- Likely
- Dimensione
- 2
In north facing terrain above about 8000', some avalanches are likely to fail on a persistent weak layer consisting of sugary faceted grains.
- Audible collapsing or "whumpfs" are a sign of unstable snow and of an active persistent weak layer problem.
- Cracking in the snow surface is a sure sign of unstable snow.
- Avalanches failing on this persistent weak layer could be triggered remotely, from a distance, or below.