Avalanche forecast

East Slopes South

Northwest Avalanche Center
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Avalanche danger

Sat
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

Dangerous avalanche conditions will develop on Friday with snow, wind, and increasing temperatures. You could trigger avalanches on steep terrain or steep terrain features. Keep your terrain choices simple and stick to low angle slopes. 

Avalanche problems

  • Storm Slabs

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

    Light snow overnight on Thursday will intensify on Friday, and snowfall will increase throughout the day. This warm, wet storm will override an unusually cold airmass leading to some uncertainty with precipitation type. We expect the precipitation to stay as snow. However, it wouldn't be a total surprise if we had a changeover to sleet, freezing rain, or just plain rain in areas near the Cascade Crest. Even if we see all snow during this storm, the warming temperatures will result in sensitive storm slabs. It will be a day to avoid steep terrain and be cognisant of steep terrain features above terrain traps such as creeks, holes, or ravines where you could be buried deeply by even a small avalanche. It will be a great day to identify red flag signs of instability, such as recent avalanches or shooting cracks while traveling on low angle slopes. If you observe a change from snow to rain, know that natural avalanches may be increasingly likely, and you should also avoid traveling under steep slopes. 

Avalanche Discussion

The deep pool of cold air on the east slopes of the Cascades will likely maintain snow throughout the day on Friday and maybe even into Saturday morning. However, while this warm, wet storm is typical for the Cascades, the extremely cold air mass is not. It could be a strange weather day with a mix of very cold temps at lower elevations, mixed precipitation types, and potentially warm westerly winds and above freezing temperatures at higher elevations. If you are traveling in the backcountry, keep your senses tuned into the weather and give yourself a wide margin of safety with your terrain choices to manage this uncertainty. 

There are limited current observations across the east-south. But adjacent zones have complicated snowpacks, some with multiple persistent weak layers. There may be similar snowpack structures in the East South, so it will be best to give yourself some extra margins of safety with your terrain choices. Avalanches that begin in the new storm snow tomorrow could step down into these deeper layers and become larger and more dangerous. Be particularly suspect of higher elevation slopes on north and east aspects where you could trigger a large avalanche that propagates widely.  

Friday could still be very cold. So make sure to prepare with extra warm layers, face shields, and ensure those grip heaters are up and running. 

Observations have been quite limited across the zone. So if you get out, please let us know what you see by submitting an observation! 

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