Over the past week we have added several feet of snow (with up to 8" of water) to our snowpack. In addition, several wind events with strong winds from the west/southwest have deposited dense slabs of wind-driven snow at the mid and upper elevations. This new snow and dense wind slabs have created dangerous avalanche conditions on mid and upper elevation slopes facing west through north and east where there is a persistent weak layer (PWL) of faceted snow down near the ground. Avalanches over the past few days have broken down to this weak layer, producing slides up to 10' deep and hundreds of feet wide.

This dangerous weakness may be disguised with none of the typical signs of instability such as cracking and collapsing. But if you do trigger an avalanche where this persistent weak layer (PWL) is present - perhaps from a thinner spot on the slope or on a steeper convex rollover - the avalanche will break down 4-6' deep (possibly deeper) and up to hundreds of feet wide. Unsurvivable.

We are moving in the right direction and ultimately the load of snow this past week should help settle the PWL problem, but for now your continued patience is required.

Instabilities from the 18-24" of new snow from the New Year's Eve storm are likely to have settled out, but you may find areas with pockets of dense snow that may be reactive, especially in exposed terrain where the new snow may have been drifted by winds. Sluffing in the new snow is also possible on steeper slopes.

What most concerns me are the northerly-facing slopes where this new snow has added stress to the deeply-buried PWL.