Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 2–3
Another winter storm arrives tomorrow and as the new snow accumulates you can trigger an avalanche on steep slopes where you find more than about eight inches of new snow. Be especially cautious of drifted northerly and easterly-facing slopes where you are more likely to trigger a larger avalanche. The most hazardous slopes are where you find firm drifted snow resting on weak layers buried two to three feet deep. The avalanche you trigger may stay in the upper snowpack, but if it breaks down into deeper weak layers it could grow larger and become more destructive. Cracking or collapsing in the new snow is a sign to look for safer slopes, but you may not see any before you trigger an avalanche. Look for safer riding on slopes sheltered from the wind without a surface slab or on lower-angle slopes.