Avalanche forecast

East Slopes North

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
1 · Low
Below
1 · Low
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Highlights

You can trigger avalanches near ridge tops in areas of stiffer, wind blown snow. Shifting wind and light snow may drift fresh slabs at upper elevations. Snowfall will favor the eastern mountains with 4-6" expected near and east of Mazama.

Avalanche problems

  • Wind Slabs

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

    You can trigger shallow wind slab avalanches on leeward sides of ridges. Pay attention to drifting patterns to tell you where slabs have been deposited. You can avoid these avalanches by sticking to wind-sheltered terrain, low-angled slopes, and steering around wind pillows and drifts. If you see cracks shooting through the snow or stiffer surfaces where the snow slides easily, move to slopes less than 35 degrees. 

    Winds have shifted between easterly and westerly directions. Triggered avalanches could spread as wide as the snow is drifted across a slope. Avalanches could be easy to trigger where new snow rests on slick crusts or weak old surfaces.

     

    (1/5/2023)

    A triggered small (D1) avalanche on the leeward side of a ridge in Liberty Bowl, next to South Early Winter Spire. SW, 7,450ft.

    Photo: NWAC Public obs

Avalanche Discussion

On Friday, Willie Webster went to the  Blue Lake trailhead and reported light to moderate blowing snow and a few small wind slab and loose dry avalanches from the past week.  Clouds were thick up to Washington Pass, but clear above that in the morning. On Thursday, observers in Liberty Bowl triggered a small slab avalanche in an area of wind-drifted snow on a leeward side of a ridge near South Early Winters Spire. The crown was 50ft wind and it ran 500 vertical feet. Other observers near Silverstar creek reported cracks shooting through wind drifted slabs just below a ridge and freezing rain at low elevations.

Observers reported a few avalanches, up to size D2, from Delancey Ridge and Spire gully that ran around Jan 1st or 2nd. These ran in recent snow layers and may have been triggered as a result of sun warming the snow and producing tree bombs and point releases.

A cycle of very large avalanches occurred December 24-27th on older weak layers that were buried in late November and early December. These weak layers are now capped with a stout crust and melt-forms from the Christmas rain event. The eastern mountains still hold a shallow and weak snowpack, but here again, the Christmas crust is capping the weak layers and adding a stronger structure. Any new snow in the eastern mountains could slide easily on the Christmas crust. 

Regions covered