Persistent Slabs
N
NE
E
SE
S
SW
W
NW
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
You can trigger small avalanches on terrain features near and above treeline where you find wind-drifted snow resting on top of old, weak snow. You may trigger a larger avalanche if you see large areas of continuous snow. The most dangerous areas are below ridgelines, cross-loaded gullies, and concave slopes with continuous snow. You can identify these problematic slopes by looking for smooth lens-shaped pillows of snow that sound hollow underfoot, crack, or collapse. If you find these signs of unstable snow, stick to low-angle terrain.