Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1–2
A Special Avalanche Advisory is in effect. Feet of recent snow and strong winds have formed thick cohesive slabs above an unusually shallow and weak snowpack. Avalanche conditions will remain dangerous through the weekend. Careful planning and conservative terrain selection is essential for safe travel in backcountry avalanche terrain.
Slopes with wind-drifted snow are the most deadly. You might trigger small slides in the newest snow, but the bigger concern is avalanches breaking on weak layers buried 2 to 3 feet deep by successive storms, which will probably not give you any warning signs. You can trigger avalanches from below.
You can find safer riding on slopes without wind-drifting at lower elevations and on slopes less than 30 degrees without overhead hazard.