Avalanche forecast

West Slopes South

Northwest Avalanche Center
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Avalanche danger

Mon
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

Sunday should be a warm and sunny day for most of the West South zone. If you take the opportunity to travel in the mountains, you may see signs of wet avalanches. If you see new avalanches with fan-shaped debris piles or rollerballs and pinwheels, avoid similar terrain features that are in the sunshine.

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Another day of warm temperatures and sunshine could further destabilize the snow surface and produce Wet Loose avalanches on Sunday. This process began in many areas on Saturday, but some slopes did not reach their tipping point. Wet Loose avalanches will be more likely on slopes over 35 degrees that see direct sunshine, and often start at a point before fanning out as they move downhill. They are also capable of entraining significant snow or even triggering slabs as they descend, sometimes growing large in the process. Take a moment to step off your mode of travel and see how deeply you are plunging into the snow. If the surface is wet and sticky and you are sinking in past your ankle, you will know that it's time to start thinking about wet avalanches. Rollerballs, pinwheels, and other avalanches with fan-shaped avalanche debris are excellent visual clues that can help you decide that it’s time to avoid steep slopes in the sunshine.

    (2/5/2022)

    Temperatures and sunshine combined to destabilize snow surfaces around the West South on 2/5. NWAC forecasters near White Pass were able to push this bit of surface snow once the conditions were right.

    Photo: Dallas Glass

Avalanche Discussion

On Saturday, NWAC forecasters at White Pass reported similar conditions to what was found in the Tatoosh Range on Friday. Variable surface conditions due to strong winds this week led to unusual loading patterns with a mix of powder, wind-drifted snow, and ice. NWAC weather stations around the zone recorded increasing temperatures and decreasing winds throughout the day Saturday, and many areas saw plenty of sunshine. Evidence of wet avalanche activity has been spotted throughout the zone by professionals and recreationalists alike, and we expect activity to peak on Sunday as freezing levels soar to ~10,000 feet. Watching how the snow surface is changing due to the warm weather should be your initial focus, but don’t forget about the recent windy conditions. Slopes that do not see direct sunshine could still be harboring some pockets of wind-drifted snow near ridgelines or rocky confined chutes for you to steer around. Cornices that developed this past week may still be fresh and tender, ready to collapse with Sunday’s warm temperatures. 

Below this past week’s storm snow, we still have the Late January Crust and its weak “facet-crust sandwich”. This layer of concern can be found 1-2 feet below the surface and the snow above it has consolidated into more of a slab in recent days. We have not received word of any avalanches on this layer at this time, but are continuing to monitor it and the load above it closely. The distribution of where this layer could become problematic is not entirely clear. The firm crust exists everywhere, but the location of the weak snow could be more likely on slopes that do not see direct sunshine at middle to upper elevations. This is not a hard and fast rule, so you need to take the time to dig down and investigate its bond and reactivity before you commit to any slope.

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