Avalanche forecast

East Slopes North

Northwest Avalanche Center
View on map

Avalanche danger

Tue
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
2 · Moderate
Open full map
Out of date — this forecast expired 6 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

You can trigger avalanches in recently drifted snow on upper elevation slopes that are steeper than 35 degrees.  In the eastern mountains, you may be able to trigger avalanches in older weak layers. For Monday, expect ongoing snow, easterly wind, and rain at low elevations.

Avalanche problems

  • Wind Slabs

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

    High Danger and an Avalanche Warning have been issued for neighboring zones. If you're traveling near the east, south, or western borders, check out the East Central and West North forecasts.

    You can trigger avalanches where you find fresh wind drifts and slabs of recent snow on leeward sides of ridges. Avalanches will be bigger and easier to trigger above treeline. Use caution on loaded slopes steeper than 35 degrees and steer around typical trigger points like convex rollovers, unsupported slopes. Recent south and east winds may have been pushed around by local terrain. As you move through terrain, pay attention to wind features and deeper versus scoured areas that can clue you into the recent direction of blowing snow. If you see cracks that shoot a long way through the snow or avalanches that break widely, move to slopes less than 35 degrees.

     On Sunday, observers in the Cutthroat drainage got cracks and a small avalanche to break on a wind-loaded southeast slope between 6,000-6,300ft. These broke about 1-1.5 feet below the snow surface on an interface of recent snow and buried surface hoar. So far it seems a wind-drifted slab is needed for this interface to be problematic. It's worth monitoring it on sheltered slopes as it may become an issue as more snow accumulates.

    (1/31/2021) Cracks and a small chunk of a slab triggered in a drift on a leeward SE aspect near treeline just east of Washington Pass. Photo: Josh Hirshberg

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    On Monday, temperatures will warm further as rain continues at low elevation. You may be able to trigger wet avalanches in steep terrain below 4,500ft. Higher in the below treeline band, you may be able to trigger moist or heavy storm slab avalanches. Use small test slopes to check how the snow slides before committing to larger slopes over 35 degrees. Use caution near gullies, or other terrain traps like cliffs where these small avalanches could be dangerous.

    (1/27/2021) Loose dry avalanches on steep solar slopes have been occurring over slick crusts in the area. Photo by Drew Lovell.

Avalanche Discussion

Light snowfall has slowly loaded a variety of snow surfaces since January 24th. On Sunday, I checked out a layer of small rounding facets over a crust that was buried on the 24th. On a southeast aspect around 5,700ft, I found the facets 54cm (about 2ft) below the surface and I got sudden test results on it, though large column tests didn't show propagation. Similar to the layer of buried surface hoar (see above) It's a good idea to monitor this layer with tests as we continue to get snow. If we get enough of a load, this layer could produce large and dangerous avalanches. If the snow comes in gradually and doesn't overload it, the layer may become a non-issue.

At upper elevations near and just east of Washington Pass, the snowpack is deep and strong, though faceted snow was observed on shaded aspects prior to the storm. Below about 5,000ft in the Highway 20 corridor, large surface hoar was observed sitting on a crust prior to the recent snow. On Wednesday, observers in the eastern mountains of the lower Methow Valley reported cracking and collapsing on older facets in snow from early January. Expect to find a shallower and weaker snowpack and more dangerous conditions in the eastern part of the zone. If you travel to areas such as the Chelan-Sawtooth Mountains, Twisp River, and Chewuch drainages, take time to dig in the snow and look for older weak layers and consider traveling in lower angle terrain and smaller terrain features.

During the ongoing Covid-19 pandemic, continue to follow the latest guidance from local, state, and federal health officials. Avoid unnecessary risks that could impact first responders and stress medical resources. Wear a mask when appropriate, practice social distancing, and consider recreating closer to home.

Regions covered