A healthy snowfall at the Pass has reset the slopes, but the storm snow will take some time to properly bond to the underlying layers, especially where the snow landed on a crust.
Storm slabs now dominate the upper snowpack, with ~30cm of warm snow sitting on a variety of old surfaces (wind crust, sun crust, surface hoar). Deeper storm slab exists in wind loaded areas.
Monday's storm brought ~30cm of heavy, warm snow at higher elevations, with a hint of rain below Treeline. This additional load will test the integrity of the deep persistent weak layer. An avalanche on this layer would be very destructive, likely run full path or further, and be of high consequence.
A natural avalanche cycle is underway (Monday afternoon) in the highway corridor as the snow falls and the temps rise. Numerous slides in the sz 2-3 range have been detected from most aspects.
Natural activity should subside quickly with dropping temps on Tues.
Warm storm snow has fallen on a variety of surfaces (wind crust, sun crust, or surface hoar), accompanied by gusty SW winds. This storm slab is presently widespread through the region.
The generally strong snowpack sits on a deep persistent basal weakness of rounding facets/decomposing crust near the ground. Uncertainty surrounds this layer; each major snowfall has the potential to finally overload this weakness, resulting in large avalanches.
The main thrust of moisture has passed the region, with unsettled weather Tues and general clearing/cooling Wed/Thurs.
Tonight: Flurries, trace snow, Alp low -14*C, mod/strong SW winds, freezing level (FZL) valley bottom
Tues: mix of cloud/sun, Alp high -10*C, light/mod S winds, 900m FZL
Wed: mix of sun/cloud, isolated flurries, Alp high -10*C, light/mod W winds, 900m FZL
