Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
4 · High
Treeline
4 · High
Below
3 · Considerable
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Highlights

Intense snowfall and extreme winds will create very dangerous avalanche conditions. You can trigger avalanches in wind-drifted snow in unusual locations, and a widespread natural avalanche cycle is likely at upper elevations. Avoid traveling in and near steep terrain while this storm plays out. Lower elevations have thin snow cover, so use caution to avoid impacts with shallowly buried obstacles. 

Avalanche problems

  • Wind Slabs

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

    The snow totals alone with this storm will be impressive, and intense precipitation rates will lead to a widespread avalanche cycle. However, rapid wind loading associated with 40-50mph winds will likely create the most dangerous avalanche conditions. These strong winds and the intense snowfall will quickly build thick wind slabs on all aspects and elevations. You may find wind slabs at lower elevations and in unusual places typically sheltered from the wind. Some atypical locations you could trigger a wind slab would be farther downslope below ridges, moderately spaced trees, or small clearings in forested areas. Cornices will also build quickly and be sensitive to triggering.It will be best to avoid avalanche terrain on Monday while this storm runs its course. A natural avalanche cycle is likely near and above treeline. Avoid being underneath steep terrain at upper elevations. If traveling at lower elevations below treeline, avoid slopes over 35 degrees and stick to wind-sheltered areas. Even in wind-sheltered terrain, triggering a storm slab avalanche on a steep slope may be likely, so make sure to give yourself a wide margin of safety in your terrain selection. Look for the red-flag signs of instability, such as recent avalanches, collapsing, or shooting cracks. 

    (3/18/2022)

    Example of a wind slab near Darland Mountain. 

    Photo: Andrew Kiefer

Avalanche Discussion

The weather is about to drastically change from what we have experienced for the last couple of weeks. The mountains will get hammered on Sunday night and Monday with heavy precipitation and very strong to extreme winds. Much of the east south zone's lower elevations are snow-free, particularly on southerly aspects. So expect the danger to be significantly greater at upper elevations and in the HWY410 and American ridge area. As the trailing cold front passes, temperatures will drop quickly, and the snow will continue to stack up. With the impressive snow totals, even lower elevations will develop significant avalanche danger by the end of the day on Monday. Areas in the zone may see over 2 feet of snow by Monday night.

A shallow, patchy snowpack exists in the southern and eastern areas of the zone, even on shady northern aspects. Some southern slopes are snow-free up to 5700ft. Use extra caution in these lower elevations where hidden obstacles may be lurking just under the new snow, and creek holes may become drifted over or hidden.

Regions covered