Avalanche forecast

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Sawtooth Avalanche Center
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Avalanche danger

Wed
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Out of date — this forecast expired 6 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Dangerous avalanche conditions exist. Triggering a very large avalanche is likely on many steep slopes. Skiers and riders should continue to choose low-angle terrain that isn't threatened by steeper slopes above. There have been many human-triggered avalanches in the past week. Most of these were triggered remotely—from below, above, and to the sides of steeper slopes.

Avalanche danger will rise late in the day and overnight. If the storm is earlier than forecast, expect to see the likelihood of natural and human-triggered avalanches increase significantly this afternoon.

Avalanche problems

  • Deep Persistent Slabs

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

    A weak layer of faceted snow is buried beneath a dense, 2.5-3.5' thick slab in this zone. Our recent observations indicate that this weak layer is showing few signs of healing. Deeply buried weak layers are difficult to deal with, in many cases the first obvious sign of instability may be the very large avalanche that you trigger. Fortunately for us, the snowpack has been giving us some direct feedback that it is unstable:

    • On Saturday, riders in this zone felt a huge collapse that they likened to an earthquake
    • Last week, Chris and I experienced a collapse that sounded like a gunshot. This occurred after we had finished our tests (unstable results) as Chris stepped out of the pit.
    • Even though many slopes in this zone had already avalanched during the Solstice storm, the more recent storm still produced some noteworthy slides (example, example).

    With the weak layer buried beneath a thick, dense slab, it may be somewhat more difficult to trigger a slide than in other portions of the forecast area. But if you do trigger an avalanche, it's likely to be a big one that will be difficult to survive. Avalanches on deeply buried weak layers are just as likely to be triggered by the first rider on the slope as the tenth rider. We urge backcountry skiers and riders to continue to choose low angle slopes and to pay extra attention to the terrain they're "connected" to. Remotely triggering an avalanche from below, above, and to the sides of steep slopes remains a very real possibility.

Avalanche Discussion

Our snowpack continues to give us clear signs that it isn't "happy". Even as the days pass since the storm last week we continue to see obvious signs of instability relating to this weak snow. Each day, observers report widespread cracking and collapsing of the snowpack, even on heavily traveled skin tracks. More importantly, observations of both natural and human-triggered avalanches continue to roll in. Our snowpack is speaking to us plainly and clearly. Our job as riders and skiers is to listen to what is being said. 

We deal with dangerous avalanche conditions by operating with wide safety margins and mentally preparing ourselves to behave that way for the long run. Today is no less dangerous than yesterday and tomorrow will be worse, not better. Stay alert to the terrain that you are traveling through and that you are exposed to from above. Recent natural and human-triggered avalanches are clear signs that the problems in our snowpack aren't healing. We need to continue to make conservative decisions in the backcountry in order to ensure our safe return home at the end of the day. 

Have a look at this video that I made yesterday describing a human-triggered avalanche, an elk-triggered avalanche, and a very large natural avalanche I observed and what they say about our snowpack.

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