Bollettino valanghe

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Sawtooth Avalanche Center
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Pericolo valanghe

Tue
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1 · Debole
Limite del bosco
1 · Debole
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In sintesi

Look for small pockets of dense, wind-drifted snow in terrain exposed to the wind; these may grow in size and become harder to identify if today's snow arrives earlier than anticipated. Rain falling at lower elevations this afternoon could produce small, natural loose snow avalanches on very steep slopes. Generally, stable conditions exist and large avalanches are unlikely. 

Problemi valanghivi

  • Wind Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–1.5

    Saturday, skiers in the Pole Creek drainage triggered two very small wind slabs (photo above/left). Yesterday, a very small natural avalanche was reported near Galena Summit and skiers on Titus Ridge produced some small avalanches by stomping fresh wind deposits along ridgelines. Moderate to strong winds blowing out of the W-SW over the past two days formed this fresh batch of wind slabs. Many of these slabs are bonding to the surfaces they are deposited on, but others may still be sensitive to your weight, thanks to the slick, icy,  and weak surfaces that exist in some areas. Today's snowfall will give the wind some more ammunition for building slabs. This is unlikely to change today's danger, but if the storm arrives earlier or more intensely than anticipated these slabs will grow in size and increase in sensitivity through the day. The new snow will also make it harder to identify older slabs visually.

    Be on the lookout for signs that the wind has been at work: drifts, dunes, and rippled snow textures are all good indicators that the wind has been transporting snow. You are most likely to find these slabs in upper elevation terrain that is exposed to the wind. If the snow you are traveling through becomes deeper or denser you've likely found one of these slabs. Cracking and/or collapsing are great indicators that the slab you've found is unstable. These slabs are unlikely to produce slides that are large enough to bury you, but they may be able to knock you off your feet or your machine. Spend a bit of time thinking about the consequences of being dragged downslope by one of these slabs.

    ADDITIONAL DISCUSSION:In very steep terrain sheltered from the wind, small loose snow avalanches are possible. These may come in a few flavors today. If you are finding cold, dry snow you may be able to trigger some small sluffs in this snow. If the snow you are skiing or riding in is warmer and has some moisture to it, these loose snow slides may pack a bit more of a punch.  The likelihood of encountering the wet variety of loose snow slides will increase significantly if today's precipitation is falling in the form of rain and wetting the snow surface.

    Curious about what's been happening in our snowpack? Catch up on what happened this past week in my latest Weekend Update!

    (2/26/2022) Skiers in the Pole Cr (Galena Summit & E Mtns zone) triggered these two very small wind slabs on Saturday, 2/26. Once initiated, it appears that they entrained weak, sugary snow that exists in the surface layers of the snowpack.

Avalanche Discussion

FORECAST UNCERTAINTY

Avalanche Danger is a direct product of both current and past weather. The season's weather produces the snowpack that today's weather impacts. We have been in an extended period of LOW danger in our forecast area, but that may be starting to change. Today, we find ourselves just south of a warm stream of very wet air. This phenomenon is known as an "atmospheric river". Unfortunately, it seems that most of the precipitation from this river in the sky will be falling just north of our area. If you were to head 100 miles north you'd be measuring snowfall in feet, not inches. As of this morning, it seems that we will only be picking up a few inches of snow and maybe some light rain at lower elevations.

The uncertainty in today's forecast is a product of this somewhat unusual weather pattern. If the moisture from this atmospheric river shifts a bit to the south we will find ourselves in the crosshairs of the associated storms. If you are traveling in our northern areas and you are finding significantly more new snow than forecast, you'll be well served to dial back your ambitions for the day. Pay attention to how much snow is falling and how the new snow is behaving. Watch for how much snow is being transported by the wind and where the wind is putting it. The Avalanche Forecast is meant as a starting point for your day, not the be-all nor the end-all. 

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