Avalanche forecast

East Slopes South

Northwest Avalanche Center
View on map

Avalanche danger

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Out of date — this forecast expired 2 years ago.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

Highlights

The dangerous wet avalanche hazard will stick with us through another day of sunshine and tropical temperatures. These unpredictable and dangerous avalanches could run naturally, or you could trigger one that breaks widely on deeply buried weak layers. Avoid traveling on steep terrain, and don't linger beneath large avalanche paths or drainages that channel avalanche debris.

Avalanche problems

  • Wet Slabs

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

    Wet loose and wet slab avalanches are still likely, with low temperatures only getting down to the mid-40F's at night and heating up to nearly 60F degrees during the day. Wet avalanches may run naturally, or you could trigger a widely propagating wet slab on deeply buried weak layers from Early February. These avalanches are notoriously tricky to predict, and the only way to manage this problem is through terrain avoidance. Stay out of harm's way by sticking to low-angle terrain, and don't linger under any large slopes greater than 30 degrees, especially during the heat of the day. Natural avalanches may run from above, so know the terrain above you and avoid areas that tend to channel wet avalanches, like steep drainages or gullies.Cornices are shedding in the warm weather as well. Falling chunks of cornice are a hazard on their own but also make an excellent trigger for wet slab avalanches. Stay well out from under these monsters, and give them a wide berth on ridgelines as they often break further back than you expect. 

    (3/16/2024)

    Snowmobilers triggered this avalanche on a southern aspect in the Ahtanum on Saturday, March 16th. It likely failed and ran on the Early February Crust. 

Avalanche Discussion

Yet another day of hot, sunny weather with light winds drives this persistent avalanche forecast. The prolonged warm weather means that large wet avalanches are still a very real concern, and the spring-like shed cycle will continue. On Saturday, there was a close call where snowmobilers triggered an avalanche in Ahtanum that failed on these deeply buried weak layers. This indicates the potential for large and destructive avalanches as meltwater moves through the snowpack. The overnight temperatures aren't allowing for a solid overnight refreeze of the snowpack at mid and upper elevations, so don't expect avalanche conditions to improve much on Tuesday. 

Before this warm-up, we had a widespread, persistent slab problem. There was a fatality two weeks ago in Ahtanum meadows, and in the neighboring East Central, we saw multiple large human-triggered persistent slab releases last week. This prolonged warm-up will likely awaken this older problem and is an excellent reason to dial back your terrain selection. Instead, seek out sunny ridgelines or flat meadows far away from large avalanche paths.  

As with any warming event, there is a high level of uncertainty as to where, when, or even if this scale of avalanche activity will occur. On the other hand, big natural avalanches should not be taken lightly. When planning your routes, consider that this is one of the times when an 'unexpected' avalanche might occur.

You can add to the avalanche forecast. Submit your observation here.

Regions covered