Avalanche forecast

West Slopes Central

Northwest Avalanche Center
View on map

Avalanche danger

Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
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Out of date — this forecast expired 6 years ago.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

Human triggered avalanches are possible as we continue to receive more snow.  Reports from nearby areas on Tuesday revealed reactive yet unpredictable avalanche conditions.  Stay off slopes steeper than 35 degrees until the snowpack has time to adjust to the added load.

Avalanche problems

  • Storm Slabs

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

    You could trigger a slab avalanche in the recent storm snow. Observers found varying amounts of reactivity on steep slopes, some of which were unaffected by wind. Wind will increase the hazard as you climb in elevation. Textured surfaces, pillows of recently drifted snow and new cornice development are signs that wind has deposited more snow onto a slope which will make the slope more reactive. With recent uncertainty, make conservative travel decisions and stay off slopes steeper than 35 degrees. 

    A small storm slab avalanche

Avalanche Discussion

A stout December 9 crust formed over our existing snowpack last week after 2 inches of rain fell. Avalanches are currently limited to the 2 feet of new snow above the crust, which will continue to grow in the coming days.  Below 4000ft the snowpack is thin, so watch out for open creeks, trees and rocks.  

In the Stevens Pass area weak sugary snow was found in the  layer above the December 9 crust. Surface hoar from Dec 12 was found overlying that in some spots.  There is a lot of uncertainty about these weak layers’ reactivity and how widespread it is. To investigate you can dig down easily through the layers above the crust to see if there is a horizontal stripe of large feathery crystals, or a broader swath of loose sugary grains closer to the crust. If you find either of these give steep slopes in the area a wide berth.

Regions covered