With sparse snow cover, there is a high level of variability in snow depths but not in the snow structure. Snowpack depths range from bare to 4” to 32” depending on aspect, elevation, slope configuration and whether slopes are shaded or non-shaded.
The “snowpack” in the Rock Creek area is shown below. The snow structure is similar in shallow north aspects. The sun crusts at the snow surface and within the “snowpack” assist the faceting process.
The depth hoar of today is the same depth hoar of a month ago because depth hoar has been shown to recycle over and over. Depth hoar and facets are increasing in size and the texture is becoming coarser due to the water vapor moving through the snow and encountering barriers to vapor transport in the form of multiple sun crusts. Ned Bair recently reported 2 meter ECT’s propagating on steep shaded north aspects in the Red Lake area.
The snowpack contains a several persistent weak layers: depth hoar from October and November snow, a thick layer of large facets resulting from the biggest snowfall of this miserable year, December 3-6, and a couple of thin layers of facets formed from mid and later December snow.
As the dry, clear weather continues, so does the faceting process. Possible weather scenarios include small cold “inside slider” storms that bring only a few inches of new snow, adding to the smorgasbord of weak layers. This happened last winter after the December storms. The scenario we all hope for is a multiday, multi footage event that will open up the backcountry and add water to offset the current drought. The downside is that big snows will bury these persistent weak layers, create storm and wind slabs and create unpredictable avalanche conditions. Given a choice, I’ll take big storms and avalanche conditions over shallow snow anytime.