Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

Thu
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

Avalanche danger is decreasing but you can still trigger slab avalanches in steep terrain holding wind drifted snow. Steer around trigger points like convex rolls, unsupported terrain above or around cliffs, or wind loaded slopes just below ridgeline. Look out for wet avalanches if the sun makes an appearance. 

Avalanche problems

  • Wind Slabs

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

    As the new snow settles and gains strength the places where you might trigger one become less in number and limited to places where the wind created stiffer slabs.  Westerly winds could create new wind slabs as well. 

    Use cornices, wind affected snow surfaces and pillowy-looking drifts to identify areas of wind slab. Soft new snow might obscure the clues you normally use to identify loaded slopes. Gauge the depth and stiffness of new snow and assess the bond of wind slab layers as you gain elevation. Given the amount of new snow available for transport it might just be best to avoid terrain where you observe recent or active wind loading

     

     

    (3/14/2023)

    Shallow human triggered slab avalanche in terrian with light wind loading. NNE aspect @ 5100' in the Baker Backcountry/West North.

    Photo: Matt Lubar

  • Loose Wet

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

    Wet avalanche activity could be a factor on Wednesday with 3-6" of new snow and a good chance of seeing some sun in the afternoon. Pay attention to slopes overhead and look for signs of instability like pinwheels, rollerballs, or snow shedding from trees and rocks. Don’t linger directly under steep slopes if you start seeing any of the above. Also, be aware of cornices overhead. They deserve plenty of space, especially as it warms up through the week.

    (3/14/2023)

    Lots of rollerballs and fresh wet loose avalanches occurred with sunshine in Snoqualmie Pass.

    Photo: Katie Warren

Avalanche Discussion

Avalanche activity varied between the zones adjoining West Central. Observers in Snoqualmie Pass found small wet loose avalanches and other signs of instability related to warming and sun. Alos noted were a handful of slab avalanches that were triggered by cornice fall or tree bombs and one very large avalanche below Chair Peak that likely ran during the height of the storm.

Numerous human triggered avalanches to D1.5 were reported from around West North. Most were quite shallow (6-12" deep) and occurred where either the wind or sun stiffened up the uppermost layers of new snow to make a reactive slab. Signs of avalanches that released during the peak of the storm were visible everywhere if you looked close enough. Debris piles covered with snow, filled-in crowns, and avalanche paths full of wet, frozen chunks were found throughout the zone on all aspects and at all elevations.

No significant observations came from Stevens Pass other than signs of wind transport, wind slab and some cracking. No observations were submitted from West Central.

New snow amounts likely range from 2-3' in many areas across the zone. Southerly aspects should have a breakable crust topping the snow surface while shaded aspects hold cold dry snow and excellent riding conditions up and down the west slopes.

Regions covered