Persistent Slabs
N
NE
E
SE
S
SW
W
NW
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
You can trigger an avalanche on north, northeast, and east-facing slopes near and above treeline where stiff wind-drifted snow rests on weak snow near the ground. If you notice signs of instability in the snowpack such as shooting cracks or collapsing, then consider moving to slopes less than about 30 degrees or a different aspect. Below the treeline, the snow cover is generally too thin to trigger a dangerous avalanche.