Quick report
- Red Flags
- Wind Loading, Cracking, Poor Snowpack Structure
- Red Flags Comment
- <p>We caused some locallized cracking on the Jan/Feb interface, 1-30 rime-crust capping thin layer with recently developed near surface facets and graupel, also some SH at this interface. Some shallow areas (<2') had very weak, well developed and dry 3mm+ facets under a few inches of fresher snow.</p>
Here are a couple examples of the localized cracking we caused. The cracks, up to around 6" deep were failing on a sugary weak layer at the Jan/Feb interface.... Developing wind slabs are likely to fail on the same layer.
Snowpack
- Instability Comment
- <p>Wind slabs developing and likely an issue in and around terrain features and on the lee side of major ridges.. Stiffened and recently built-out cornices also something to be wary of along the ridges.</p> <p>I noticed a widespread shallowly buried persistent weak layer at the Jan/Feb interface. Main concern here are sugary faceted grains formed near the surface during the cold early February high pressure system, but a capping rime-crust, graupel and surface hoar all add to the mix... The problem with spacial variability comes when you find constants, or less variation. Weak layers with the same properties widespread across a slope probably means avalanches will be more likely when a slab matures.</p> <p>The existing snow structure is not very good either, with a currently dormant weak layer from early January consisting of fist-hard faceted snow.</p>
We found very nice smooth and fast shallow powder conditions. A bit of riming action going on, and rime blowing out of trees made it seem like a blizzard at times.