Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Wed
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Out of date — this forecast expired 5 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Watch how the weather is unfolding and driving avalanche problems throughout the day. East winds could develop fresh slabs or combine with cool temperatures to marginalize the sun’s input. The snowpack on the volcanoes may need a little more time to heal before you step into consequential terrain.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Wind-loaded terrain is the most likely location for you to trigger a lingering slab on Tuesday. These may have formed during the previous storm or be freshly developed by gusty east winds. East wind events often create slabs in different areas than you may be used to and frequently produce more mid-slope and cross-loaded pockets. Look for these pockets on convex slopes or near rocky features such as the base of cliffs or confined gullies. Actively blowing snow will be your easiest indicator that new slabs may be forming and can also help clue you in to where they are lurking. Textured surfaces or small drifts behind trees or rocks are other visual clues that you can use to help identify wind-loaded features to avoid. 

    With cold dry snow sitting above a crust, loose avalanches may provide you with more direct feedback as you travel. These sluffs should be easier to trigger on steep slopes over 40 degrees and you won’t want to get surprised and swept off your feet near terrain traps or other consequential terrain. 

    (2/1/2022)

    Using visual clues can help you identify wind-loaded slopes to avoid.

    Photo: Andy Harrington

Avalanche Discussion

The West South just received its most significant snowfall in a couple of weeks with the volcanoes outpacing areas closer to the crest by about 6” or more. Regardless of your location in the zone, the new snow is expected to be generally right-side up and sitting above a thin melt-freeze crust (2/19). This interface may look a little different based on aspect but is generally found an inch or two above the easily identifiable Valentine’s Day Crust. In some areas, you may not be able to discern between the two. On the volcanoes the new snow could be more layered, giving it more potential points of failure. Take your time and do your homework about conditions before committing to a slope.

On Tuesday, temperatures are expected to be chilly and east winds are notoriously cold. That said, we are anticipating the sun to make an appearance in the afternoon. As we creep closer to spring, its influence, and ability to destabilize the surface grows. The expectation is that the cool temperatures and breeze will keep most of the cold dry snow in place, but you could find some natural loose avalanches fail during this period, possibly triggering a lingering slab as they descend. 

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