Snoqualmie Pass

Saturday will be the proverbial “calm before the storm.” You should find generally safe avalanche conditions thanks to surface crusts and well-settled snow. If you head to the tops of the higher peaks or into more extreme terrain, you might find a lingering unstable wind-loaded pocket.

A significant winter storm is knocking on our door, but it won’t get here in time on Saturday to increase the avalanche danger. So, while you may see an inch or two of snow accumulate in the afternoon, it shouldn’t pose any hazard. 

If you’re going to find an avalanche on Saturday, it would probably be near the summits of the higher peaks or in cliffy/unsupported terrain. A few pockets of unstable wind-loaded snow may still linger in these areas. Keep your eye out of firm pillow-like slabs that you may want to avoid. 

Mostly clear skies Friday evening should allow the wet surface snow from the recent sunny weather to freeze. This will form a new crust on most southerly aspects. This should all but eliminate avalanche concerns in these areas. The same clear skies could allow a fresh crop of surface hoar to develop. On shaded slopes, this will add to the weak snow that developed Thursday night. As we head into a stormy period, take note of what’s on top of the snow. An old avalanche adage is, “Today’s surface is tomorrow’s weak layer.” As the snow starts to fall in the afternoon, it will hide these potential weak layers. 

Below the surface the snowpack has become much more aspect dependent. On sunny slopes, numerous melt-freeze crusts and a generally shallower upper snowpack sit over the prominent Early February Crust (EFC). You may occasionally find facets just above the EFC, but they haven’t been as concerning on these warmer aspects. In shaded terrain, the snow is deeper over the EFC and contains more notable layers, including the potential for buried surface hoar and facets. These layers haven’t produced any avalanches in the Snoqualmie zone but are on our radar as the storm door opens. 

While there might not be much in the way of avalanche concerns on Saturday, you might bump into some travel issues. Breakable crust, frozen rollerballs, small piles of old debris, and open creeks could make travel challenging. However, observations still suggest that northerly aspects continue to hold pockets of cold dry snow.