Persistent Slabs
- Alta quota
- Limite del bosco
- Sotto il limite del bosco
- Probabilità
- Unlikely
- Dimensione
- 2–3
In terrain that held snow from October, the chance lingers for backcountry travelers to trigger persistent slab avalanches up to four feet deep at the higher elevations. The old snow surfaces from October can be found on northwesterly to easterly aspects at the upper elevations and northerly aspects down to an elevation of 8,500 feet. While the likelihood of triggering these slabs is decreasing, the consequences remain high. Some slopes that held snow from October are stable, and others may remain suspect. This uncertainty is based on elevation, aspect, snow depth, the presence or absence of crusts and how the slope was loaded. In this situation, snow pits are useful for identifying snow structure. However, when evaluating the snowpack, remember that stability tests should be used to test for signs of instability, and the absence of significant test results should not be used as an excuse to ski a slope.