Persistent Slabs
- Alta quota
- Limite del bosco
- Sotto il limite del bosco
- Probabilità
- Possible
- Dimensione
- 2–3
Persistent weak layers continue to exist on various aspects and elevations throughout the forecast region. The Jan. 2 persistent weak layer includes buried surface hoar, near surface facets, and/or a facet/crust combo and has been responsible for the majority of our recent avalanche activity. The Dec. 19 rain crust and basal depth hoar on the ground have also been reported of failing on some avalanches that have stepped down to these lower weak layers. With each passing storm, these weak layers become buried deeper in the snowpack. Areas where these weak layers are closer to the surface; steep rocky slopes, complex terrain, any shallow snowpack areas, may be more likely locations to trigger a persistent avalanche.
People can remotely trigger these avalanches from above, below, or to the side of a slope, and they often break much wider than expected. Recent avalanches, snow surface cracking, snowpack collapse, or whumpfing sounds indicate unstable persistent slabs, but fewer obvious clues may exist today. Utilizing non-avalanche terrain, with no steeper connected slopes above you, can greatly reduce your exposure to this avalanche problem.
(1/15/2024)
Large natural avalanche between Lincoln and Anderson Peak-thought to have occurred on Sat Jan 13. See the size of the crown relative to the people.