Avalanche forecast

East Slopes North

Northwest Avalanche Center
View on map

Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
1 · Low
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Out of date — this forecast expired 3 years ago.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

You can trigger small avalanches at upper elevations where the wind has drifted recent snow.  Look out for pillow-like slabs below areas of blowing snow, sharp drifts, and textured surfaces. Stormy weather overnight will give way to a clearing and cool temperatures on Saturday.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1

    Strong winds built fresh slabs in the classic places along exposed ridges, at the tops of chutes, and near the base of cliffs. If you find signs of instability like cracks shooting through the snow or wind drifts that break easily with the weight of a person, stay off of leeward slopes over 35 degrees. Look for visual clues like sharp wind drifts and stiffer snow surfaces. Steer around fresh drifts and stick to lower-angle or wind-sheltered slopes. 

    A warm and windy storm on Friday brought a few inches of snow with strong southwesterly winds. Snow and wind will taper off by Saturday morning. Expect enough new snow and wind transport for fresh wind slabs on leeward slopes, especially on north through southeast aspects. Many of the recently identified weak snow surfaces exist lower in the terrain and in sheltered areas. However, if you find the intersection of old weak snow and fresh wind slabs, they could be triggered easily or in surprising ways.

    (12/22/2023)

    Cracks in recently wind transported snow near Harts Pass.

    Photo: Willie Webster

Avalanche Discussion

Clouds should break by with weak, filtered sun by afternoon. Some steep south slopes may warm slightly, but wet avalanches shouldn't be a significant hazard. 

A storm on Friday brought about 4-5" of new snow and stronger winds to the zone. Observers in the Harts Pass and Willow Creek areas noted significant blowing snow, fresh wind features (6-8" deep), and cracks in the new snow.

This new snow fell on a variety of old surfaces, but two seem more prominent. Surface hoar was seen particularly on shaded aspects. On Wednesday, observers on Rainy Pass found it on the surface as well as buried in the top 8" of the snowpack. In steeper, more southerly terrain, a surface crust likely formed. As you travel, take note of where they survived by using small hand pits.

Similarly, older layers of buried surface hoar and the 12/10 crust (below ~6000ft) may be found slightly deeper in the snowpack. The prominent 12/7 atmospheric rain crust continues to be an excellent snowpack marker for tracking variations in the upper snowpack across the terrain.

Regions covered