Avalanche forecast

West Slopes Central

Northwest Avalanche Center
View on map

Avalanche danger

Fri
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
Open full map
Out of date — this forecast expired 7 months ago. You’re viewing past conditions, not the current bulletin.

Highlights

Avalanche danger increases with elevation, transitioning from smaller wet slides to larger and more dangerous dry avalanches. Stick to lower-angle terrain, especially as snow depths start reaching eight inches or more over the crust. Dangerous, complicated conditions exist right now, so give the new snow time to settle before heading out onto steep slopes in areas where there's more than a few inches over the old snow crust. 

Avalanche problems

  • Storm Slabs

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

    Tricky weather and avalanche conditions are in play today, making this a good day to keep things simple and stick to gentler terrain. Upper elevations could hold 18+ inches of new snow over a crust, with strong winds forming thicker drifts and more reactive slabs capable of producing large, dangerous avalanches. Rising temperatures also mean even non–wind-loaded slopes may have poor layering and be sensitive to human triggers.

    Avalanches will be limited to above the old snow surface. In some spots, weak snow may linger on that surface —especially at shady upper elevations and farther east in the zone. Some slides could be surprisingly easy to trigger, or even occur naturally, and these weak spots may vary widely from slope to slope, or even be only a few feet apart. You won't be able to identify where these spots are. 

    If you see natural avalanches, avoid runout zones as well. Otherwise, dial back to lower-angle terrain once new snow reaches about 8 inches over the crust. Pay close attention to upside-down snow (heavier snow over lighter layers)—whether from wind or warming—which is a clear sign to avoid steep slopes.

    Example photo: Slab avalanches will increase in size and become more reactive as you gain elevation on Thursday. 

  • Loose Wet

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

    As temperatures rise, expect increasing wet loose avalanche activity at mid elevations. When snow first becomes wet, rollerballs or natural avalanches are likely (especially Wednesday night). Snow that’s already wet may need a trigger—like falling snow chunks from trees or rocks, or a person on a steep slope—to slide.

    As you move from lower into mid elevations, keep an eye on surface wetness. If the snow is wet and there’s more than a few inches over the crust, human-triggered slides are possible on steep slopes. Rollerballs or natural avalanches are clear signs to avoid similar terrain, including runout zones.

    At lower elevations, only the very upper reaches may hold enough moist snow over the crust to produce small wet loose avalanches on steep slopes with a human trigger.

    Example photo: Rollerballs are indicators that wet loose avalanches could run. Avoid steep slopes and terrain beneath them if you see an abundance of these, or avalanches. 

Avalanche Discussion

The old snow surface is mostly a firm, bumpy crust. With only a little new snow, it likely won’t slide easily—but once a thicker slab builds on top, that rough crust won’t matter much, and avalanches become likely. If the soft snow moves, expect a hard, unforgiving surface beneath you instead. New snow is also masking hazards like bare patches, rocks, trees, and glide cracks.

After more than two weeks of warm, dry weather, it’s good to see a change. By Wednesday evening, some areas received nearly an inch of water—translating to up to a foot of snow at upper elevations, but mostly rain lower down. Snowlines will rise, with another 6-8 inches possible Wednesday night and yet another 6-8 inches up high on Thursday. Most of the snow will fall in the morning, with strong winds, before snowfall and wind taper later in the day. 

Fresh snow is exciting—but remember, it also brings avalanches that could seriously harm or kill you if you don't travel appropriately for the conditions. 

Regions covered