Southeast Mountains

Previous northerly winds have left hard slabs on the lee sides of terrain features. You can reduce your chance of triggering a slab avalanche by avoiding terrain features that look smooth, hard, and rounded from previous wind loading. The best snow quality for skiing and riding can be found in wind-sheltered locations on the north half of the compass. In those areas, enjoy the riding while keeping an eye out for small loose snow avalanches on steep slopes. 

Check out the weekly summary for a more in-depth read on recent events. 

Both forecast areas have the same primary avalanche problem. In the SE Mountains persistent slabs remain possible to trigger and in the NW Mountains, the same avalanche problem falls in the unlikely category. This is due to the weak layers that those hard slabs are sitting on. In the SE Mountains it is more common for those hard slabs be be sitting on more notable weak layers. Either way, these hard slabs are not going to be easy to human trigger and it will likely take just the right slope, just the right location on that slope, and/or a bigger load. 

Following the brutal wind event at the start of the week, we can break down the travel advice into two categories: wind-sheltered terrain and wind-exposed terrain.

Wind-sheltered terrain: Avalanche hazards are small and easy to manage.  The snow surface is soft, and growing weaker each day.  On the north half of the compass, you'll be able to trigger loose dry avalanches on slopes steeper than 35 to 40 degrees.  Some slopes may be weak enough now that sluffs will start to gouge deeper and entrain more snow than expected.  This observation from Snodgrass sums it up.  

Wind-exposed terrain: The potential avalanche hazards are larger.  The snow surfaces are firm and variable.   Many slopes were wind-eroded and offer safer options: look for wavey, heavily textured snow call sastrugi to identify those slopes.  Concave and leeward catchments from northerly winds caught the drifting snow and formed dense slabs. Some of those slabs formed over weak layers or added stress to weak layers deeper in the snowpack.  We have more evidence of these issues in the Southeast Mountains, including frequent collapses and notable avalanche activity in Upper Cement Creek, explosive results yesterday at CBMR, and a skier caught and carried on Mt. Emmons.  The Northwest Mountains experienced the same wind-loading event, though the recently buried weak layers and over-stressed structures appear to be less common on a regional scale. This Ruby Range observation (click through the media gallery) from before the wind event demonstrates several layers and structures of concern on what are now leeward aspects from northerly winds.  You might find unstable structures on slopes that were shallow and weak all season and recently experienced significant loading, like this large avalanche on the west face of Gothic.   The easiest way to manage the problem reliably in both forecast zones is to simply stay off of the slopes with obvious wind loading from the recent wind event.