Persistent Slabs
N
NE
E
SE
S
SW
W
NW
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Dangerous conditions exist in near and above treeline areas where strong winds are drifting snow over a weak snowpack. Avoid travel on slopes steeper than about 30 degrees in these areas. You can trigger a dangerous avalanche that breaks on weak layers near the ground on northerly and east-facing slopes. Assess the snowpack carefully before traveling on and under steep slopes. Avoid areas where you see signs of recent wind drifting, such as fresh cornices, smooth pillows of snow, or a hard, sculpted snow surface. You will find safer conditions in wind-sheltered areas in places where the snowpack is more than about 5 feet deep.