Avalanche forecast

East Slopes Central

Northwest Avalanche Center
View on map

Avalanche danger

Wed
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
Open full map
Out of date — this forecast expired 4 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

The atmospheric river has one more punch to deliver overnight on Monday with continued heavy rain and high elevation snow. Dangerous avalanche conditions will persist through the day on Tuesday, and triggering large avalanches will remain likely. Avoid travel in steep terrain and don't linger beneath large avalanche paths. 

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2.5

    Heavy rain with warm temperatures will continue, and it will remain easy to trigger large wet avalanches. There is also the possibility of continued natural wet avalanches in some isolated areas, probably most concerning during the overnight hours of Monday as snow levels peak. Snow that feels wet and heavy and rollerballs are the first indications that wet loose avalanches are possible. These wet avalanches will likely involve the recent snow, but they could potentially still step down to the Valentine's Day crust, becoming very large wet slabs. Once these large wet avalanches get moving, they can run great distances following ravines and gullies into lower elevations and can be incredibly destructive. Avoid traveling on steep slopes where you can trigger and get caught in these wet avalanches. Also, avoid lingering underneath any large avalanche paths.

    (1/13/2022) Large wet loose avalanches like this will still be possible on Tuesday.

    Photo: Katie Warren

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2

    If you manage to make it through the rain at lower elevations into alpine zones above around 6000ft, you may find a return to dry snow avalanche concerns. Heavy precipitation overnight may fall as snow at these elevations, adding to already significant storm snow depths. Strong winds will also distribute new snow into deeper drifts on lee aspects. While many of these large alpine starting zones likely avalanched on Monday, these new storm slabs may still be large enough to bury or kill you. Let the snowpack adjust to these rapidly changing conditions and avoid steep slopes and starting zones, especially in wind-loaded areas near ridges. 

    (11/23/2021)

    Example of storm slabs at upper elevations. 

Avalanche Discussion

The atmospheric river brought 1-3 inches of water to the east-central zone, with higher amounts likely in areas close to the Cascade crest. 10-20 inches of snow fell in many areas before precipitation changed to rain. While natural avalanche activity was widespread on Monday, isolated areas may still slide naturally as heavy rain continues into the morning hours of Tuesday. Even areas such as Mission Ridge Ski area with shallow snowpack experience small natural avalanches. Avalanche hazard will likely be highest in the morning on Tuesday as precipitation tapers off and temperatures cool ever so slightly in the afternoon. Travel in the backcountry will likely be deep, soggy, and challenging. There is uncertainty with the likelihood of very large avalanche activity, so continue to give large safety margins between you and the runout zones of large avalanche paths. 

Areas such as Mission Ridge and Blewett Pass have a limited snowpack, and avalanches in these areas may be smaller. Mission Ridge Ski Patrol reported a saturated snowpack, so if you are sinking deeply into wet snow, stick to lower angle slopes. Even small avalanches can have high consequences if you get carried over rocks, stumps, or into open creeks. 

Regions covered