New Snow Depth
4.5'
New Snow Density
Medium
Snow Surface Conditions
Dense Loose
Snow Characteristics Comments
Our first goal was to evaluate the distribution and sensitivity of the storm slab. Recent changes in precip type and rate were changing the storm snow into a more dense over less dense layer. The dense snow was roughly 4" thick and Fist+ in stiffness, resting on 6" of less dense Fist hard snow, with 6-8" of 4Finger hard snow at the bottom of the storm slab. This soft storm slab was evenly distributed throughout the elevation range and on all aspects that we observed up to 8,500' and produced light cracking in steeper terrain. Where we were, the storm slab was still too soft to propagate cracks more than 10-15 feet, but likely that would change dramatically when you get into drifted snow.
Our second objective was to try to get a handle on whether this new load was becoming active on the weak layers in the upper snowpack. We found Surface Hoar and Facets buried down 40-50cm in a half dozen looks in the snow on Westerly aspects in Mill D North. Our Compression Tests consistently indicated on this weak layer, with Sudden Collapse results. Our ECT's were much more variable, with 3 x ECTN results with fractures arresting within the weak layer, and 1x ECTP result, each from different profiles, but in similar terrain where we found the weak layer down 40cm. We thought it would be possible to trigger this deeper persistent slab, but the location and distribution of the problem are tough to nail down.
