Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

Tue
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
1 · Low
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Highlights

We have a lot of uncertainty around how Monday will pan out, but no matter what, conditions will be wet and windy. Increasing temperatures will result in wet avalanches reaching into the upper elevation band. This is a day to avoid steep terrain, and if you encounter any natural avalanches, avoid travel beneath large slopes as well. 

Avalanche problems

  • Loose Wet

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

    Rising snowlines will result in wet loose avalanche activity, even into the upper elevation band as the day progresses. As freezing levels rise, wet avalanche activity will shift from lower to mid elevations before transitioning to the bottom part of the upper elevation band as the day progresses. Snow at higher elevations, which so far has remained lighter and drier, will probably be the most reactive as it gets wet. 

    In general, much of the recent snow we've received is heavier, rather than the more favored light, fluffy snow initially getting wet and sliding, so we're not sure exactly how much avalanche activity will result. At lower elevations, the snowpack is already saturated, so we don't expect much to happen. Your largest concern might be wet avalanches running down to those elevations from overhead. 

    Feel how wet the snow around you is- can it form snowballs? Can you squeeze water out of it? Are you noticing any rollerballs or wet loose slides running down steep slopes? If you notice any snow sliding or rolling downhill, avoid traveling on steep slopes, and consider steering around the bottom of large paths that hold enough snow to slide.  

    Example photo: Wet loose avalanches in variable snow cover at lower elevations like this may be something you could encounter on Monday.

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1.5–2

    Slab avalanches could occur at mid or upper elevations on Monday. These avalanches may be moist, especially as snow transitions to rain and the surface layer gets heavier. We're not sure how many natural avalanches will occur, but we suspect it's possible that they could happen. Human-triggered slab avalanches are likely, so it's best to avoid traveling in steep terrain on Monday. 

    Avalanches will probably break in the new storm layer, around a foot or more deep, but there's a chance they could break deeper into recent storm layers. If you notice any red flags, such as long, shooting cracks or recent natural avalanches, it's time to take a step back and avoid travel beneath large snow-covered slopes as well. 

    Example photo: Long, shooting cracks like this are indicators that a slab avalanche will occur on a steeper slope. 

Avalanche Discussion

Rising temperatures will likely be the largest variable in avalanche activity on Monday. Snowlines are expected to start at about 4500ft earlier in the day, before shifting to 6500ft or possibly even higher by the end of the day. Meanwhile, we'll be receive around 1.5 inches of water during the day. At the top of our upper elevation band, this will amount to well over a foot of new snow. Near the top of our lower elevation band, we may get a few inches of heavy snow before a transition to rain occurs, saturating the snowpack even more. 

Early-season conditions exist, and snow cover is extremely variable. Snow may be inconsistent from where you step out of your vehicle to when you gain elevation and reach smoother, more substantial snow. If you get caught in an avalanche on Monday, there's a good chance you'll get taken for a rough ride, potentially impacting rocks on the ground along the way. 

Snow has been slowly and continuously building since Friday.  Snotel sites are reporting around 4" of water as of Sunday evening. Temperatures fluctuated throughout, with a mix of rain and snow at lower and mid elevations. Especially after the next few days we expect that we'll find less snow at the lower elevations than before this storm. Meanwhile, although we haven't received information in the last few days, we suspect there is several feet of new snow at upper elevations. 

Regions covered