Persistent Slabs
- Hochgebirge
- Waldgrenze
- Unterhalb der Waldgrenze
- Wahrscheinlichkeit
- Likely
- Größe
- 3
I will continue to avoid mid and upper elevation northerly facing slopes. These slopes have a buried persistent weak layer of weak, sugary facets near the ground that could fracture and produce slab avalanches 4-6 feet deep and hundreds of feet across. Avalanches could be triggered remotely, from a distance or from flat terrain under steep slopes. It's a very different situation at lower elevations and on south facing slopes where this persistent weak layer near the ground doesn't exist. The photo below is a close up of what the faceted snow looks like. Notice the striations or straight lines that form when the snow crystals change into a weak faceted crystal. Cold temperatures like those in the last couple days cause a temperature gradient in the snowpack and these sugary snow crystals to develop. I am noticing rapid development of faceted snow at low elevations these days, especially where the existing snow is still shallow.