Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 3
Mid and upper elevation northwest through easterly facing terrain has the perfect recipe for deep and dangerous avalanches. In the terrain highlighted by the blue in the locator rose graphic (to the left) - you will find a dense slab roughly 2 to 4 feet deep that sits on top of very weak faceted snow at the ground (strong over weak). The weekend storm has added more weight and stress to this already fragile set up and conditions today will be more active as a result. Right now there are two strategies for avoiding this problem:
1. Simply avoid this snow structure by staying on southerly aspects, where faceted snow doesn't exist.
2. Or travel on slopes no steeper than 30° with nothing steeper above, below or adjacent to you. Unfortunately, it looks like this problem is here to stay for awhile. The good news: Southerly facing terrain will have good turning and riding conditions today where you don't have to deal with this avalanche problem.
Picture: Northerly facing slope at 9,500' in elevation. Showing the slab and weak layer set up.