Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Unlikely
- Size
- 1.5–2.5
Weak snow formed during a dry period in November is well preserved within the snowpack. The triggering of slabs that lie above this layer has become less likely and limited to steep terrain above 8500 feet that has a north component in aspect. Slab failure is hard to predict as a slope can be tracked several times before a particularly thin, weak spot is impacted. If triggered, these slabs will be hard with depths of 1 to 3 feet. Evaluating the snowpack layering to the ground on a specific slope can provide insight to this extent of this weakness.
Significant variability in the snowpack exists throughout the zone between the Wyoming, Salt, and Snake River Ranges. Submit an observation to help us tune into your local area and improve our forecast ability.
(12/21/2023)
Here is a good example of the terrain where triggering a persistent slab is most likely. These avanches occured during out last storm cycle.
Photo: Alex Drinkard