Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Unlikely
- Size
- 3
We've got a series of storms headed our way and this may be enough additional weight needed to wake up our problem child, a persistent weak layer of snow, now buried close to the ground in our early season snowpack. And while it's been over a week since we've heard from this layer of snow, in reality little has changed on this front and that's why it's call "persistent". You see, anything "persistent" in a snowpack takes a long time to heal and that's where it gets a little tricky. As the weak layers grow slightly stronger and get comfortable in their own skin, you can ride some steep slopes, often without incident, giving us a false sense of snowpack stability. However, all we need to do is find one weakness, maybe around a bush or rock that we can't see buried underneath the snow, collapse the pack, and now we're staring down the barrel of a scary avalanche. The way I'm avoiding this scenario is by simply avoiding the terrain where this setup exists- steep, upper elevation, north facing slopes that harbored snow prior to the big Thanksgiving storm. With plenty of safe options, there's no reason to pull on the avalanche dragons tail. But wait... here's the good news. There's a lot of terrain to ride today and not have to deal with unmanageable avalanche conditions, IF you chose slopes that had NO old snow prior to the big Thanksgiving storm.
Welcome back!
JG was near the Duchesne Ridge yesterday and his beautifully detailed pit profile above clearly shows our current setup. Click here to view more on JG's travels and to read his very sage advice.
Meanwhile, I was on the North Slope on Tuesday and though my snowpit stability tests suggest a strengthening snowpack (good news), failures continue to revolve around weak, basal snow (bad news). What this means is... it might be harder to initiate a slide, but the piece of snow you trigger will dangerously break to the ground.
Knowing where the weak snow exists is the ticket. Taking our own advice, Tuesday my partner and I simply steered clear of upper elevation, shady slopes facing the north half of the compass, got out on sunny slopes with no old snow, and still had a blast.
