Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1.5–2.5
Avalanches will be large enough to bury or injure you on slopes where you find slabs of snow deeper than about 12 inches. Thick, dangerous slabs of snow rest on top of weak snow on slopes that face west through north to southeast at all elevations. Place lots of room between you and any suspect terrain because you can trigger a slide from lower-angled slopes adjacent to or below avalanche paths. Below the treeline, avalanches might be smaller but can result in a rough ride if you are carried through trees or over rocks. Signs of instability in the snowpack, such as shooting cracks, collapsing, or recent avalanches, may or may not be present to warn you. You can find safer travel on slopes less than about 30 degrees in steepness or aspect without a weak layer.