Avalanche forecast

West Slopes North

Northwest Avalanche Center
View on map

Avalanche danger

Wed
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Out of date — this forecast expired 3 years ago.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

Wet avalanches of all shapes and sizes are the main concern on Tuesday. Reduce your exposure to large cornices and glide cracks. Avoid travel on or below steep slopes if the snow is wet, soft, and unsupportable. Small avalanches in dry snow should be on your radar anywhere you find more than a few inches of new snow and signs of wind transport.

Avalanche problems

  • Loose Wet

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

    Small but widespread wet loose avalanches were reported Monday in the terrain around the Mt. Baker Ski Area. Continued warm temperatures and increasing sun will keep them in play until temperatures cool. You are more likely to see wet avalanches on slopes facing the sun but shaded slopes have warmed enough you might see them on those aspects as well. Lots of slopes have produced wet loose avalanches but that doesn't mean there can't be more.

    They are more likely to occur when the snow is wet and unsupportable. You might even trigger one on a steep slope.  Wet loose avalanches commonly initiate in rocky or treed terrain. Keep an eye on what is above you and limit time spent below slopes where you suspect or witness signs of wet avalanche activity.

    Example of a wet loose avalanche starting in steeper terrain above.

  • Glide Cracks

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    2–3

    Glide avalanches, wet slabs, and cornice fall all become hazards during extended periods of above freezing temperatures. The likelihood of seeing one of these avalanches is low but the consequences are high if one occurs above you. In addition to being large and powerful, they can also trigger larger avalanches in much deeper layers.

    Limit travel below large cornices, definitely don't have lunch under one. Also, be on the lookout for glide cracks where the entire snowpack is beginning to slide on the ground below. There isn't much you can do about these types of avalanches other than stay out of the way.

    (12/15/2022)

    Example of a glide crack on Herman from earlier in the winter. Note the yawning crack where the slab (aka the entire snowpack) is slipping on the smooth rock. Also, look for a "wrinkled" looking snow surface where the gliding slab is pushing on the snowpack below.

    Photo: Jason Speer

Avalanche Discussion

There wasn't much in terms of reported avalanche activity Sunday. A skier did fall through a snow bridge spanning a large glide crack on Table Mountain. There was no sign there was a glide crack below the bridge and other skiers and riders had already traveled across in the same spot. They fell a good distance in the crack but were not injured. While not an avalanche problem it's another reminder that warm temperatures are changing and weakening mountain features. 

Monday was the fourth day with temperatures continuously above freezing. This shift in conditions also requires a shift in mindset. While dry snow avalanche problems like storm and wind slabs will still be with us, warming-related avalanche problems should be a consideration any day it’s not cold and stormy. 

Glide, cornice, and wet slab avalanches are just straight-up difficult to forecast. The setup for these avalanches to occur - prolonged warming, glide cracks, and sagging cornices - is coming together. If you see one of these it will probably be large and deadly to anybody in the way. But determining the likelihood is a near roll of the dice. Despite Moderate danger at all elevations, you may see zero avalanche activity or you may see a D3 triggered by cornice fall. Don’t be surprised by either outcome.

Regions covered