Persistent Slabs
- Alta quota
- Limite del bosco
- Sotto il limite del bosco
- Probabilità
- Possible
- Dimensione
- 3
Once initiated, a small avalanche can break into weak layers of snow buried in the mid portion of our snowpack, resulting in a slide that gets quickly out of hand.
The good news is... early season snow means we're off to a great start, the Uinta's are white, and travel is mostly easy. The bad news is... two weeks of dry, bitter cold weather during mid November, created a layer of very weak, sugary facets on the snow surface which are now preserved underneath several storms and buried in the mid portion of our snowpack. Here's where the rubber hits the road and what makes things tricky right now... any avalanche that fails near our new problem child, the persistent weak layer or (PWL), is gonna break deep and wide and it's gonna be dangerous.
Unless you take your shovel out, dig down and investigate a bit, you can easily get lulled into a false sense of snow stability because the snowpack has gained a substantial amount of buoyancy and will feel strong and solid underneath us. But remember- hard, dense snow resting on weak, sugary snow can give us a false sense of snow stability, allowing us to get out further onto a slope before it fails and brings the entire roof down on top of us.
Obvious signs of unstable snow include cracking, collapsing, and whoomping noises as well as natures freebie... natural avalanches!
Upper elevation, north facing structure
Mid elevation Southeast facing structure