Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

Wed
Alpine
4 · High
Treeline
4 · High
Below
3 · Considerable
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Highlights

High avalanche danger exists on this windy and stormy day. Natural avalanches are likely, and human-triggered avalanches are very likely. Avoid steep slopes and terrain underneath steeper areas in the avalanche runouts as well. 

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    2–3

    Very dangerous avalanche conditions exist, and this isn't a day to try and tiptoe around on steep slopes- instead, steer clear of all avalanche terrain. We expect that there will be a large avalanche cycle in the early morning hours, but snowfall rates won't let up much during the day, so natural avalanches are expected to continue during the day. Spending any time beneath large avalanche paths isn't recommended. 

    Danger will be higher at mid and upper elevations, where there's already a deeper snowpack, and large to very large avalanches are very likely with a human trigger. Lower elevations don't have as much snow to start with, although it's starting to grow deeper. It's still likely that you could trigger a large avalanche at these elevations, so continue to follow the same travel advice. 

    Example photo: Large and very large avalanches a very likely to fail with a human trigger, or naturally avalanche on Tuesday. 

    Photo: Adam Ü

Avalanche Discussion

We've been finding an underlying weak layer of facets above the 12/30 crust. This was buried 2-3 feet deep during a storm Friday night. At least some of the avalanches in the natural avalanche cycle that occurred early Saturday morning probably failed on this layer. Avalanches during this storm may fail shallowly in storm slab layers, in wind slabs, or also as deep as the 12/30 crust vicinity, which might be 6ft deep in some places on Tuesday. If you were to get out on steep slopes, thinner areas are where a human might be able to trigger the underlying weak layer. All these points are strong indicators of the same thing- Tuesday is a day to travel conservatively in the backcountry. 

The storm slab avalanche problem is all-encompassing for new snow avalanche problems. You can expect to see an uneven fresh new snow coating, with thicker, wind-loaded deposits in some spots and stripped areas in others. This will be much more evident as you gain elevation, although even at lower elevations, you will probably be battling the wind as well. 

We're forecasted to receive over an inch and a half of water overnight, probably well over a foot of snow. Just a little less is expected to come in during the day. This storm could total over 3 feet of snow up high. Strong to extreme sustained wind speeds will make the day even more exciting. Deep snow immersion is a real concern as the snow deepens as well- beware of getting too close to trees!

 

Regions covered