Persistent Slabs
N
NE
E
SE
S
SW
W
NW
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
The most dangerous areas are near and above treeline slopes where you find around 10 inches or more of new or drifted snow. Easterly upslope winds will form deeper drifts on atypical, westerly-facing slopes. An avalanche triggered on a wind-loaded slope can break wider and step down into weaker snow near the ground, making a more dangerous avalanche. Avoid places where you see evidence of drifting like fresh cornice growth, lens-shaped snow pillows, or where the snow feels hard underfoot. If you see cracking in the snow or hear rumbling collapses, retreat to slopes around 30 degrees in steepness.