Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

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

You're most likely to trigger an avalanche where wind drifted the foot of snow we received Monday night into thicker and heavier deposits. Feel beneath you for deeper drifts, search for rippled or pillowlike surfaces, and avoid these areas on steep slopes. When in doubt, steer around steep terrain. If the cloud layer is thin or the sun pops out, wet avalanches could run in the new snow layer. 

Avalanche problems

  • Wind Slabs

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

    As you climb higher, the avalanche danger will increase. Most avalanche activity will probably be limited to the surprisingly thick layer of new snow that fell Monday night. Avalanches are most likely to occur on wind-drifted slopes. With the foot of snow that fell, drifts may have redistributed into deposits up to two or more feet deep.  

    Search for wind-textured or smooth, pillowlike surfaces. Feel for heavier snow beneath you. You're most likely to get deeper drifts around rocky outcroppings, in gullies, or on the leeward side of slopes. The new layer is soft and shallow enough that you can dig down to see how easily a wind slab slides on the layer beneath it. 

    Avoid traveling on steep, wind-loaded slopes. If you have any uncertainty, avoid traveling in all steep terrain on Wednesday. 

     

    Example photo: You could trigger a wind slab avalanche on steep slopes on Wednesday, similar to this one here. It might be hard to identify the slab on the surface, but here you can tell that one side is much deeper than the other, so clearly has been wind-affected. 

    Photo: Pete Durr- USFS Backcountry Ranger

Avalanche Discussion

Although unlikely for Wednesday, if the sun pops out or cloud layers are thin, we might end up with many large, wet loose avalanches that could run naturally, and possibly initiate slabs. Given the amount of light, dry snow that just fell, even just a little warming or sun might be enough to tip the scale and cause avalanches. We expect the main, preliminary warming event to occur on Thursday, but don't let your guard down- if you start noticing any wet, sticky snow in areas where there's several inches of the new layer, it's time to shift to lower-angle terrain away from steep slopes. 

There's still a very small chance that a glide avalanche, cornice fall, or chunk of snow perched on a rock face could fail. Water has continued to drain from the snowpack since the warm atmospheric river last month, when a large, wet avalanche cycle occurred. Since then, slightly cooler temperatures lowered the likelihood of deeper avalanches. Although chances of this type of avalanche occurring are low, the consequences are high if you're caught. Consider traveling quickly beneath any of these features if you encounter them. 

Backcountry travelers were out in the zone during the day on Sunday (Whale Peak, Sunrise Mine area). Any information from this data sparse area is so valuabled at helping us paint a better picture of the history and conditions in the area. 

Check out the media gallery for photos of some of the carnage in this and other nearby zones from the recent atmoshpheric river. The biggest concern with that period of warm weather and rain is that we haven't gotten much of a freeze since then. Temperatures are finally a little cooler, but the old snow surface is now insulated by several inches of snow and it's just not very frozen.

Submit an observation to the website or the Avy App to help NWAC Forecasters reduce uncertainty. It can be short, simple, and even anonymous. 

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