Persistent Slabs
- Hochgebirge
- Waldgrenze
- Unterhalb der Waldgrenze
- Wahrscheinlichkeit
- Possible
- Größe
- 3
Today, human-triggered slab avalanches failing on a buried persistent weak layer could be large and life-threatening. During the last storm, heavy snowfall and drifting by winds from the west overloaded slopes plagued by widespread buried layers of weak, sugary snow or facets and feathery surface hoar that developed during the prolonged December dry spell.
- Avalanches could be triggered remotely, from a distance, or worse, from below.
- Collapsing or whumpfs and shooting cracks indicate unstable snow.
- Avalanches are possible even when there are no obvious signs of instability.
- With unseasonably warm temperatures and rain, the low-elevation snowpack is soft and saturated. Triggering a wet avalanche in terrain with poor snow structure, like the steep banks next to the Logan River, is possible.