Avalanche forecast

West Slopes Central

Northwest Avalanche Center
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Avalanche danger

Wed
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
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Highlights

7:30AM Update: We received about three times more snow than was expected overnight. Human-triggered small and large avalanches are likely at upper elevations, where we may have received a foot of new snow overnight.  Avoid travel on steep slopes, especially if wind-loaded.

As you gain elevation, you'll notice more wind-effect in the few inches of snow we receive Monday night and Tuesday. Your biggest chances of triggering an avalanche are in those new wind-drifted deposits. If they start nearing 6 inches or deeper, consider steering around those drifts on steep slopes. 

Avalanche problems

  • Wind Slabs

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

    Update: Up to a foot of snow fell at mid and upper elevations Monday night. As you climb higher, snow depths will grow and danger will increase. Human triggered avalanches are likely. Most reactive slabs will probably be in wind-drifted snow, but even non-wind-loaded areas could avalanche with a human trigger, especially if temperatures increase during the day. 

    Old text:

    Most avalanche activity will probably be limited to the new snow that falls Monday night and Tuesday. If we get a few inches, plus wind, that could be enough to produce small or medium sized avalanches, especially as you gain elevation towards more exposed, wind-affected terrain. 

    Identify actively blowing snow, and watch to see where it lands. Search for wind-etched surfaces or smooth, pillowlike areas. You're most likely to get deeper drifts around rocky outcroppings, in gullies, or on the leeward side of slopes.

    You should easily be able to identify the new drifts over older snow layers. In spots where you find deeper and heavier deposits, consider steering around steep slopes. 

    (1/9/2023)

    Example photo: Small wind slabs like this could fail on steep slopes with a human-trigger. Mountain Loop Highway.

    Photo: Irene Henninger

Avalanche Discussion

If the sun pops out or at the snow/rainline interface you might encounter rollerballs or small wet loose slides. Any small avalanches, if they do occur, aren't expected to be large enough to have any consequence. 

It's not completely out of the question that a glide, cornice, or chunk of snow perched on a rock face could produce an avalanche. The last time we heard about one of these occurring in neighboring zones was Friday night. Water has continued to drain from the snowpack, and slightly cooler temperatures are further reducing chances of this occurring. Although there is a very low likelihood of this type of avalanche occurring, 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 relatively nice period of weather 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. 

Several inches of rain fell in last week's atmospheric river, resulting in a large avalanche cycle. Check out the media gallery for photos of some of the carnage in this zone and other nearby zones. The biggest concern with this recent 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 a few inches of snow and it's just not very frozen.

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