Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 2
Recent storm snow has buried weak facets from the January dry spell, creating a tricky slab problem. Avalanches 8 to 18 inches deep are being reported daily and are propagating wider as the snow settles and the slab stiffens. Some of these avalanches have been triggered from a distance.
Avalanches are most likely to fail on slopes where wind deposited additional snow; however, the signs of obvious wind-drifting we normal look for may not be present as snowfall from Thursday fell without much wind and covered our usual indicators. Slopes where you find a cohesive slab of snow above this layer of sugary facets is where you can trigger an avalanche up to 2 feet thick and more than 200 feet wide. This structure is easy to identify with the naked eye if you get your shovel out and dig down just a couple feet. See example below.