Avalanche forecast

West Slopes Central

Northwest Avalanche Center
View on map

Avalanche danger

Thu
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
Open full map
Out of date — this forecast expired 3 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Wind-drifted snow deposits near and above treeline are where you're most likely to trigger and get caught in a dangerous avalanche on Wednesday. Identify thicker, wind-affected snow drifts and steer around those features on steep slopes. Those will be the most consequential, but you will probably also encounter and trigger loose snow avalanches in steep terrain running dry, or wet if the sun shines intensely on southerly slopes.  

Avalanche problems

  • Wind Slabs

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

    Steep, wind-loaded terrain is where you're most likely to get into trouble on Tuesday. Many avalanches reported in neighboring zones on Monday failed in shallow slabs a few inches to 6 inches deep, producing small avalanches. To the north, some were natural and some were human triggered. Although less likely, both the West North zone and Stevens Pass each reported one human-triggered large slab avalanche failing closer to 2 feet down. 

    Feel for an "upside down" snow structure, with heavier snow sitting on top of lighter snow as you travel. You might also be able to visually identify wind-affected snow, by noting textured surfaces. Pay attention to obvious clues like cracking or recent avalanches. If you notice any of these characteristics, steer clear of nearby slopes steeper than 35 degrees.  Wind is expected to increase throughout the day, so you may also see active loading indicating areas to avoid, and it may also mean that slopes you were on earlier may produce an avalanche later in the day. 

    (2/28/2023)

    Shooting crack on a wind drifted slope. Avoid steep nearby terrain.

    Photo: Matt Primomo

  • Loose Dry

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

    An overarching loose snow avalanche problem of dry and wet may be more applicable for Wednesday. An abundance of cold, dry snow has fallen in the last few days- over a foot of it exists at mid to upper elevations, which is ripe to sluff off steep slopes, especially if you step out onto them. This will happen in non wind-affected areas. Snow in the top couple inches may slide, but it could entrain snow a little deeper, and run faster and farther than usual. Make sure to stay alert to this if you enter steep terrain, and have an exit strategy off to the side of a slope if a sluff is flowing rapidly downhill. 

    We may see enough sun that it could moisten any low-density snow on steep, sunny slopes, causing wet loose avalanches. This could start on easterly slopes in the morning before shifting southerly and then west facing in the afternoon. There's about a 50/50 chance we'll be seeing enough sunlight for this to be a problem, so keep it on your mind during your outing. If you start noticing rollerballs or small wet loose avalanches, steer clear of steep slopes on similar aspects. 

    Sluffs, or dry loose avalanches, seen last week, running far and fast in the cold, dry snow. 

    Photo: Jere Burrell - Guided Exposure

Avalanche Discussion

Since Sunday we've received around a foot of snow, and it's also been windy, especially at upper elevations. This is a day where there's a lot of variability within the zone and from slope to slope. What you see in one location might vary quite a bit from other areas. Use this forecast as a starting point to further evaluate slopes during your day's outing. If you travel anywhere in this zone, whether you see any avalanches or not, please send in an OBSERVATION so that we know more about the conditions in the area. 

Regions covered