Quick report
- Cracking
- isolated
We dug two hand pits at 4300' on a SSW aspect. The first failed on isolation, the second with a pretty minimal pull. Both failed on the same interface, about 18 inches down, and about 3-4 inches above the 1/3 crust, on what appeared to be an intra-storm density change. I would characterize as Sudden Planar for both. We dug two additional hand pits higher up, 4900' SW. These took a lot more effort to produce failure, and the resulting fracture was non-planar. We noted wind slab up high, near ridge line, which cracked when backpacks were dropped on it at transition. We were not on a slope that was steep enough to slide, but the wind slab was definitely present. When skiing down, we noted little instability in the upper snowpack, but remained cautious because of our hand pit results. As we got lower, we did get some movement on small, steep rollovers. Whether you want to call it sluffs or small avalanches, the storm slab did seem to be the culprit. On small features, this was manageable, but wouldn't have wanted to be in larger, more open terrain with that snowpack setup. Overall, this tracks with the hand pit observations, where it was easier to trigger the storm slab at lower elevations. I hypothesize that warmer temps caused these layers to become denser and "slab up" a little more. It may also have something to do with differences in the 1/3 crust at different elevations, but these failures seemed to be occurring on a different interface, higher up in the snowpack.