Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

You could still trigger a surprising slab avalanche in the new snow layer 1 to 2 or more feet deep. Upper elevation shady slopes are where you're most likely to trigger one, and we recommend avoiding steep terrain where slopes have trees, rocks, or cliff bands, which would result in a dangerous ride. Warmer temperatures and more sun may cause wet loose avalanches as the day warms up on Monday. 

Avalanche problems

  • Storm Slabs

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

    The neighboring West North zone had several human-triggered storm slab avalanches on Saturday, and one on Sunday. Conditions there are very similar to much of the West Central zone.  The layer we're concerned about is slowly strengthening, but you can still trigger an avalanche on upper-elevation slopes, most likely north-facing, which formed weak layers during the long period of high pressure before the new snow fell. Wind redistributed the weak layer, scrubbing it from ridgetops and possibly redistributing it downslope, resulting in lower crown lines than you might normally see.  People are still finding weaknesses and triggering avalanches within the storm snow as well, a few inches to a foot deep. Plenty of graupel was noted during this last storm, contributing to some of these potential sliding layers. 

    Slopes that are greater than 35° and especially ones that don't provide a smooth runout, aka areas with terrain traps, are locations we recommend avoiding at this time. If you trigger an avalanche you don't want to take a ride through trees or over a cliff. You can also quickly dig down with your hand to the relatively shallow layer to check out how well the layers are bonding before committing to a slope. If you notice whumphing or long shooting cracks these are strong indicators to avoid nearby steep slopes. 

    (3/14/2023)

    A human triggered slab avalanche similar to what you may encounter on Monday. 

    Photo: Irene Henninger

  • Loose Wet

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

    We expect to see a bit more sun and slightly higher temperatures on Monday. South-facing slopes and lower elevations will probably start the day with a crust, but this may break down and we could get resulting wet loose avalanches on the southern half of the compass on Monday. 

    (3/25/2023)

    This wet slide continued for another 300-400ft below these trees. S 4,700ft - Stevens Pass.

    Photo: Public obs

Avalanche Discussion

Wind will start picking up Monday afternoon and you may see snow redistributing. Avoid freshly drifted locations as wind slabs build, especially at higher elevations. The wind may also help to keep snow surfaces cool, slowing the moistening of snow surfaces. 

Continue to maintain springtime awareness of gaping glide cracks and looming cornices. As soon as the day gets a little warmer they'll start moving faster and gravity may win out with these unusual features, pulling them rapidly downhill.

The newer storm snow fell Thursday-Friday and amounts to 1 1/2 to 2 + ft over the old snow layer at upper elevations. The weak layer appears to be improving in strength and avalanches are occurring less frequently, but we're not ready to completely trust the layer yet. Even if chances of triggering an avalanche are lessening, taking a ride could still have a bad outcome. 

Regions covered