Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 2
As temperatures continuing warming today and the last weeks cold snow begins to settle, pockety slabs will become touchy, reactive to our additional weight, and may break deeper and wider than you might expect.
The heat is on and it's effecting our snowpack as last week's low density storm snow is settling and becoming more cohesive (a slab). It's not a rapid change, but the weak, sugary, near surface facets (NSF) formed during the January/February dry-spell are coming out of their dormancy and back to life. Walking around on the bed surface of a recently triggered slide and digging right next to it, makes me realize just how weak the NSF have grown over time. Man, it's nothin' but shugga... baby, and it's not going to take much of a load before the wheels come off. The weakest snow I've found is on east, north, and northeast aspects, especially on mid and upper elevation wind sheltered slopes. Here's where it gets tricky... large swaths of upper elevation terrain facing the north half of the compass were blasted by the winds prior to our recent storms and weak snow distribution is spotty at best. That means you'll need to evaluate each slope on an individual basis.
A sidebar HEADS UP - It's easy to be complacent because conditions aren't too dangerous, and avalanches may not be too big. HOWEVER, an avalanche fatality earlier this month in Montana near West Yellowstone is an example of how a relatively small avalanche can be deadly. That avalanche was 4-11 inches deep and 75 feet wide. Read more HERE.