Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 2
There are booby-traps out there, friends.
The January/February drought resulted in very weak facets along the snow surfaces and it was clear that once it started snowing in earnest, we would have avalanches. The problem is that although it has snowed, it hasn't snowed in earnest, so that the avalanches, although widespread (pretty much all of the north part of the compass at all elevations) are relatively small and pockety. But relatively small and pockety can still kill you, especially if you're hungry for powder and especially if you're surprised by the avalanche, which is common whenever avalanches can be triggered at a distance.
The weak snow is easy to find. The issue is that the overlying slabs of cohesive snow are not as easy. Many slopes just have powder on facets while many others have powder snow that hides a slab below. Bruce Tremper used to call this "sucker snow". Which are which? Cracking and collapsing often accompany the existence of poor structure and avalanche conditions, but not always. My observation in Broads Fork yesterday looks at this more in depth HERE. An observation in the UFO Bowls by Conover and Jonas is HERE
What to Do?
- If the game is rigged, choose not to play. In other words, owing to the high uncertainty and the nature of the problem, choose low angle slopes with nothing steep above. We rode low angle northerly terrain yesterday and it was the best in two months.
- Choose aspects that do not harbor the PWL: we know that northwest through east aspects harbor the PWL. West is uncertain and variable. Southwest to south to southeast do not harbor the PWL and these aspects will ride nearly as well today.
