Avalanche forecast

Banner Summit

Sawtooth Avalanche Center
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Avalanche danger

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

Triggering wet snow avalanches will become increasingly likely on slopes facing the sun. Even if skies are cloudy, if the snow surface feels wet these slides are on the menu. Expect these avalanches to become large and destructive in big terrain, moving fast on slick crusts. Pockets of wind blown snow can still be triggered in exposed, upper elevation terrain. Cracks shooting out from your skis or machine are a clear sign of an unstable slab.

Avalanche problems

  • Loose Wet

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

    Today will bring bands of cloud cover that could keep the snow cool, or have the potential to trap heat and warm snow surfaces. It does not take much to melt fresh snow. As the sun pops out and/or heat is trapped beneath warm clouds and melts the new snow, wet snow problems can quickly turn on. Even if the sun is mostly behind thin cloud bands, pay close attention to if the snow surface is wet or melting. If you are sinking into wet snow or can squeeze water out of a snowball, wet snow issues are likely. Be aware not only of snow you are moving through, but the snow on the slopes above you. 

    Most of today's wet snow avalanche activity will involve only the snowfall from the past few days, running far and fast on top of slick crusts from last week. However, the underlying snowpack is still saturated from intense rainfall on Wednesday and Thursday. Slides that gouge down into wet snow and flank out as slabs will be much larger, more destructive, and less predictable. 

     

    ADDITIONAL DISCUSSION - WIND SLABS: Moderate winds and up to 2 feet of snowfall built dense slabs in exposed terrain at upper elevations. These slabs will remain reactive to your weight today, but should be relatively small and isolated. Older slabs that formed at the start of the storm have had some time to bond, but you won't be able to identify them visually thanks to the new snow on top. You're much less likely to trigger one of these, but they are larger than the most recent batch of slabs. 

    (4/6/2024)

    Wet loose avalanches observed in Meadow bowl in the Sawtooths on Saturday afternoon.

    Photo: Ben VandenBos

Avalanche Discussion

While today will bring more bands of clouds than yesterday, wet loose avalanches are still possible. Thin cloud bands have the potential to either keep the sun off the snow or trap heat through a greenhouse-like effect and cause surface warming. It is hard to predict which of these will happen, but luckily it will be easy to identify. If the snow is becoming moist or wet, wet snow issues are certainly on the menu. The likelihood of trigger slides like these will increase throughout the day. Wind slabs still are a concern, as an observer triggered a 2' deep slab near 9500' on a SW aspect in the Baker Creek drainage two days ago. 

There is a thick sun and rain crust beneath our recent snow at middle and upper elevations. The snow that accumulated on top of this crust has started to melt and bake on, but will be shed easily today when the sun returns in force. While it will take a bit of time for things to really warm up, once they do we will see quite a bit of shedding, likely lasting through the day and following the sun around the compass. Anticipate wet loose slides to become large and destructive in large terrain. Slides running on top of the crust will move fast and far. The recent snow has settled into a dense slab in many locations and these surface slides may flank out and have a slabby character to them. While this describes our wet snow problem, high rain lines and shifting rain/snow precipitation patterns during an intense series of storms last week leave more uncertainty in other portions of the snowpack.

When you head into the mountains today you will find wildly variable conditions as you climb in elevation and change aspects. Pockets of dry snow, wind-scoured and loaded pockets of snow, melted and refrozen crusts — the list goes on. Moderate NW winds have the potential to build new wind slabs at upper elevations where there is fresh snow available for transport during the day today. While there was a decent freeze overnight, with high rain lines last week the snowpack has the potential to still be harboring enough free water to make avalanches run farther and wider than you may expect. or even on colder aspects. An observer reported a notable a large wet avalanche in the Northern Sawtooths yesterday in N/NW facing terrain near 8500. Even if you are entering N-facing terrain, note that the walls of terrain like N-facing couloir still face east and west, and can receive sun and warm enough to cause shedding. 

Manage the complexity, variability, and unpredictability posed by our transitional snowpack by building a wider safety margin into your travel plans today. The cloud cover today leaves some uncertainty around our wet loose problem, and the best way to address this is through continued observations throughout your tour. Pay attention to the snow you are moving through, the snow on the slopes above you, and the snow you will have to move back down through at the end of the day. If you're feeling the snow become moist or seeing natural wet slides even if it's cloudy, the wet loose concern is growing. Pay attention to how much snow is being melted. Be ready to step back from the plans you make, and have an exit strategy if things start to melt down. It may be springtime, but we are not at LOW danger just quite yet. The spring transition period is one of the easiest times to get complacent: the weather is friendly, but the snowpack still demands respect and attention. Get out there, enjoy the conditions, and let us know what you see. But don't take the seasonal shift as an invitation to turn your brain off. 

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