Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

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

The avalanche danger will be minimal in the morning and will quickly spike as temperatures warm and the sun melts the surface snow. Wet avalanches will likely occur as the day warms and they could be big enough to bury or kill you. Plan your travel to stay out from under cornices and to be off of sunny slopes before wet avalanche activity begins.

Avalanche problems

  • Loose Wet

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

    Expect the warmest temperatures in almost 2 weeks and enough sun to maintain the threat of wet loose avalanches. You may be able to trigger avalanches and they could release naturally from overhead terrain. Avalanches could gouge into deeper layers of snow, becoming big enough to bury or kill you.

    Give yourself plenty of options of lower angle or shaded terrain. Make sure you have plenty of time to be off of steep slopes before they get warm and weak. Take note of warming and wetting at the snow surface or previously supportable crusts melting and becoming weak. If you observe signs of instability like rollerballs, pinwheels, or very small avalanches, move to more shaded or lower angle slopes.

    (4/23/2022) A large, (D2) natural, wet loose avalanche on Mt Herman, SE Photo: Andy Harrington

  • Cornices

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2

    Watch for falling cornices with warming throughout the day. Cornices could trigger bigger avalanches and can be big enough to be dangerous on their own. When traveling on slopes, stay well out from under cornices that could be looming above at the ridgetop. Don't linger on slopes with overhead cornices and make sure you pick safe locations to stop and regroup. If traveling on a ridge, be careful not to wander too close to the edge or onto an overhanging cornice. They frequently can break much further back than anticipated. 

    Recent wind drifted slabs and cornice growth formed during the week.  Sunday's warming temperatures and sun are the perfect recipe to bring them crashing down onto slopes below. While it may be difficult for people to trigger wind slab avalanches, a cornice fall could be enough to cause one to break and slide. 

    (3/27/2022)

    An example of a cornice failure and glide avalanche on Huntoon Point from last month.

    Photo: Lee Lazzara

Avalanche Discussion

On Friday and Saturday, observers in the Mt Baker side-country reported triggered and natural wet loose avalanches. Natural avalanches were mostly small, though one large avalanche was observed on Saturday on Mt Herman (see photo above). On Wednesday, observers in West North reported skier and snowmobile triggered shallow slab avalanches in terrain steeper than 40 degrees. Extensive wind transport was noted on the higher peaks with less below 5500'. Most recently, a large natural wind slab was near the Rainbow Glacier on the north side of Mt Baker (see photo below).

Isolated, buried surface hoar was responsible for at least one avalanche earlier in the week in the Mt Baker side-country. While it's now unlikely to trigger an avalanche on this layer, it's worth keeping in mind. You may be able to find it buried on northerly, mid and upper elevation slopes where it managed to survive sun, warmer temperatures, and wind.

This is NWAC’s last daily avalanche forecast for the 2021-2022 winter season. Mt Weather Forecasts will continue until May 1. Make sure to check our Spring Avalanche Statement for information and travel advice. NWAC will continue to track snow and weather conditions. Large storms and/or widespread avalanche cycles may cause us to issue special avalanche bulletins, avalanche warnings, or other spring statements to keep you informed.  You can help your backcountry community by continuing to submit observations of avalanches, snow, and pertinent weather to our site.  Have a fun and safe spring recreating in the mountains! 

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