Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Fluffy snow is covering up buried weak layers that could produce a dangerous and deadly avalanche. You are not likely to hear, see, or feel any signs of instability, but the potential for avalanches exists regardless of what you experience on your tour. We know it's tempting, but the only way to stay safe is to avoid steep and open slopes facing east, west, and north.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2

    A 1.5-3.5 foot slab rests over weak layers formed in January. This setup resulted in multiple human-triggered avalanches last week and continues to produce failing test scores and whumpfs (would-be avalanches if the slope was steeper). Though these layers are variable in their distribution and sensitivity over the landscape, they are generally capable of producing avalanches on shaded slopes at the mid and upper elevations. 

    You can't dig and assess your way out of this problem. Yes, many slopes will not produce avalanches, but you don't have a crystal ball or X-ray vision to know which ones will.  The evidence of this problem is widespread and convincing and the only way to navigate this is through disciplined terrain choice. Plan a route in forested or low-angle terrain and avoid steep and sustained open slopes on the northern half of the compass.  

Avalanche Discussion

The problem persists. We have been tracking the 1/10 complex (facets and crusts) and the January Drought Layer (JDL - facets or facets and crusts) and over the past week plus we have seen avalanches, whumpfs, and unstable snowpack tests on these layers. Virtually every hamlet within the West South has reported some clear sign of instability. We know you want this problem to disappear. So do we, but the snowpack doesn't care. Though this problem may be a bit more stubborn to trigger as the days stack up since the last storm, appreciate that the snowpack has shown little to no signs of improving stability. Meanwhile, the consequences of a slide haven't changed one iota. Don't let your guard down and remember that low-angle and forested slopes are holding fantastic snow right now.

A slight uptick of wind and sunny skies should put a few more things on your radar on Monday. There is a chance for some active wind slab formation if easterly winds ramp up. Look for blowing snow and textured surfaces, and steer clear of slopes where you see those signs. The volcanoes are the most likely candidates to see wind speeds high enough to form fresh slabs. In addition, some loose avalanches could shed from steep slopes and rocky features facing the sun. Whether wet or dry, these point releases should be relatively small but could become a problem if they knock you off your feet in the wrong spot. 

Finally, with clear skies forecast for most of the week, some folks may take the opportunity to venture further afield. Keep in mind that most of our observations come from the usual locations relatively close to trailheads. You could find different, potentially more reactive, persistent slab conditions if you push further into the mountains.

Regions covered