Avalanche forecast

East Slopes North

Northwest Avalanche Center
View on map

Avalanche danger

Fri
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
Open full map
Out of date — this forecast expired 3 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Watch for wet avalanches on sunny slopes and any steep terrain with soft, moist surface snow. Cornices could fall as the sun comes out and temperatures warm. Don't linger under cornices and move off of steep slopes with weak, moist snow.

Avalanche problems

  • Loose Wet

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

    Watch for wet avalanches on steep slopes where you find soft, moist snow on the surface. If you see fresh rollerballs, move to lower-angle or shadier terrain. Use extra caution if you see avalanches gouging below surface layers.

    Thursday has the greatest potential for wet avalanches of any day this week. Warm temperatures and sun could warm surface snow enough to melt old crusts. Wet avalanches could occur on most slopes, with an emphasis on the sunny, east through south through west aspects at mid-elevations. 

    (1/24/2024)

    An example of roller balls as a sign that the snow is warming up. If you see these starting to run down the hill, it's a sign that wet avalanches could occur with further warming. 

    Photo: Josh Hirshberg

  • Cornices

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

    Be aware of any overhead cornice hazard, especially if you don't have a clear view of the terrain above you. When traveling on ridges, keep plenty of distance from the edge and be sure that you're traveling on the part of the mountain and not on overhung snow.

    Falling cornices are a hazard in their own right, but they can also trigger avalanches on slopes below. Avoid lingering underneath these behemoths, especially as the sun warms them. The exact timing of cornice falls is tricky and unpredictable. Sometimes, they can fall well after the warmest time of day. 

    (1/25/2024)

    An example of a natural avalanche (D1.5) was initiated by cornice fall during a warm-up in January. Poster/Pika Pk NE, 7,2000ft

    Photo: North Cascades Mountain Guides

Avalanche Discussion

For Thursday, expect the most warming of surface snow due to the sun and temperatures that we've seen in over a week. While unlikely, avalanches due to wind-drifted slabs are worth keeping in mind. 

Observers have reported small skier-triggered and natural wind slab avalanches over the past week, primarily from upper elevations. The last skier-triggered wind slab avalanche occurred on the 18th on a north aspect at the upper elevations of Silver Star Mountain. Sunny weather on last Friday formed a thin sun crust on southerly aspects at mid and lower elevations.

On shady slopes, at mid and upper elevations, there is up to 1.5ft of recent snow over a stout crust from January 31st. Observers have found a thin layer of weak facets just above the 1/31 (elsewhere early February) crust. This weak layer may have been responsible for lingering wind slab instability in some places. With future storms on the horizon, we'll be watching the weak layer as a potential culprit for avalanches. Lower elevations hold substantially less new snow, if any, over the crust and often don't hold the associated facets. 

Snowpack information is limited outside of the Highway 20 corridor and Harts Pass. Let us know what you find if you get out into the backcountry!

Regions covered