Persistent Slabs
- Hochgebirge
- Waldgrenze
- Unterhalb der Waldgrenze
- Wahrscheinlichkeit
- Possible
- Größe
- 2–3
The chances of triggering a persistent slab avalanche continue to decrease as the weak layers buried in the snowpack gain strength. Unfortunately, persistent weak layers do not gain strength uniformly across all areas. Most data from places with a deeper snowpack indicates significant snowpack consolidation and signs of instability continue to grow more sporadic. On the other hand, areas where a shallow snowpack exists still exhibit worrisome signs of instability like whumpfs, shooting cracks, and unstable snowpit tests. Specific areas with reports of a shallow unstable snowpack include the Carson Pass and Ebbetts Pass areas as well as lower elevation areas in other parts of the forecast region. Triggering a persistent slab avalanche may remain possible where the weak layer sits closer to the surface. A person hitting just the right spot (trigger point) on a slope or larger triggers like multiple people on a slope could also be problematic.
Persistent slabs behave in unpredictable ways like breaking on a slope that already has lots of tracks on it. They also can have serious consequences since they tend to propagate far and wide across slopes. This uncertain, high-consequence, low-probability problem still warrants caution. Traveling on terrain less steep than 30 degrees not connected to steeper slopes or terrain without the weak layer can provide fun recreation opportunities with significantly higher safety margins. Be patient, the snowpack conditions will improve, and bigger, steeper terrain will still be here after the persistent slab problem goes away.
