Avalanche forecast

West Slopes North

Northwest Avalanche Center
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Avalanche danger

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

We've had short bursts of precipitation since Wednesday leading to very small wet and dry snow avalanches in the last couple days. There's a slight chance you could trigger isolated, shallow slabs at upper elevations, and if temperatures warm enough, small wet avalanches might occur, mainly in the new snow layer. Very large avalanches on northerly slopes above treeline remain a concern. 

Avalanche problems

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    3

    A layer of faceted snow 4-8 feet deep is likely behind very large avalanches that occurred in the last three weeks. Though you're more likely to encounter a shallow avalanche Friday, the rare deep slab avalanche will be much more dangerous if you happen to be in the way.  It’s quite unlikely a single person could trigger one of these avalanches but they could still be provoked by a big load like cornice fall, slab, or loose snow avalanche from above. Overall the danger from these is diminishing as colder temperatures make for less cornice fall and other natural activity. That being said it’s still a good idea to not linger on big, northerly alpine slopes below cornices or other hazards. We'll have our eyes on this problem as a large system approaches at the end of the weekend. 

    (3/27/2022)

    Very large (D3) deep slab avalanche below Hidden Lake Lookout in North Cascades National Park. Likely triggered by a chunk of cornice falling from above. Northeast aspect at 6700'.

    Photo: John Scurlock

Avalanche Discussion

Observers on Thursday reported 4-6 inch small wind slab pockets in the morning. This was mainly in near treeline elevations, and there could be a couple inches more snow at upper elevations. The pockets may have settled and strengthened a bit since then. Regardless, keep an eye out for small, isolated pockets that you could trigger around rocky outcroppings, in gullies or on leeward slopes on steep upper elevation features. Avalanches in these drifts probably wouldn't be large enough to bury you if you triggered one, but if you're near a terrain trap they could still cause harm.

Very small wet loose avalanches, only a couple inches deep, occurred Thursday afternoon. Any of the moist snow will refreeze overnight and have a more difficult time sliding. A forecasted freezing level of 3000 feet on Friday means that we don't expect many wet loose avalanches to occur. However, the strong spring sun works in mysterious ways, so if there are any cloud breaks you might encounter small wet loose avalanches on steep sunny slopes. Overcast skies might also lead to moistening at lower elevations on all aspects, although your best chances of wet loose avalanches are in the new snow which fell at elevations above 3500-4000 feet. 

This spring we've jumped between wet and dry snow problems frequently, as unsettled weather patterns and temperature swings continue. In this variable weather large cornices are losing strength. Give them a wide berth. After a quick break from stormy weather today, another small storm approaches Friday night. Continue staying alert as you travel in the backcountry, as conditions are constantly evolving and we're not into a spring cycle yet. 

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