Bollettino valanghe

Bitterroot

West Central Montana Avalanche Center
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Pericolo valanghe

Fri
Alta quota
2 · Moderato
Limite del bosco
2 · Moderato
Sotto il limite
1 · Debole
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In sintesi

Large human triggered avalanches are possible at middle and upper elevations, especially on shaded or wind loaded slopes. Smaller wet avalanches are possible on steep sunny slopes. 

Dig in the snow and look out for weak layers buried 1-2+ feet deep by a stiffer slab. If you experience whumfing, collapsing, shooting cracks, or see fresh avalanches, stick to slopes less than 30 degrees in slope angle.

Problemi valanghivi

  • Persistent Slabs

    • Alta quota
    • Limite del bosco
    • Sotto il limite del bosco
    Probabilità
    Possible
    Dimensione
    1–2

    Recent snowfall built a 1-2+ foot thick slab above persistent weak layers like surface hoar and near surface facets. Triggering a large avalanche on these layers is possible. Upper elevation slopes that are shaded or wind loaded with a stiffer slab are the most concerning, but avalanches are also possible lower down in wind protected areas. A skier triggered a slab avalanche on a wind loaded slope near Gash in the Bitterroot on Tuesday. 

    Identify buried surface hoar by digging into the snowpack and looking for a thin grey line 1-2+ feet below the snow surface. Buried near surface facets will present as weak sugary snow crystals. The warm weather and sun last week likely helped destroy the buried surface hoar on solar slopes. However, these slopes could still have buried crust facet layers and wind slabs. You may not see any red flags before triggering an avalanche on these layers. If you find poor snowpack structure in your snowpit with a slab above a weak layer, or experience collapsing or whumfing, stay off slopes over 30 degrees. Persistent slabs could also be triggered remotely, from low angle slopes above, below, or to the side of steeper slopes. 

    A common trap with surface hoar is to dig high in start zones and not find it, then descend partway down the slope and trigger an avalanche on buried surface hoar. It can get destroyed high on slopes but preserved lower on the slope, creating tricky conditions for slope level snowpack assessment. If you dig a pit high on the slope and do not find buried surface hoar, do not trust that there is no buried surface hoar lower on the slope. Also, buried surface hoar can produce avalanches that fail on especially low slope angles, even below 30 degrees in extreme examples. 

    (2/10/2026)

    Snow pit on a northeast aspect at 6700 ft

    Photo: Arden Feldman

  • Loose Wet

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

    Peak wet avalanche sensitivity has passed, but small wet loose avalanches in the recent snow will still become possible on steep, sunny slopes today. They could run far on the slick, crusty bed surface below. Surface melt-freeze crusts on south aspects will have to break down for wet loose avalanches to occur. If you find yourself in mushy, wet snow or start seeing rollerballs, consider avoiding avalanche terrain. Remember that even small avalanches can have serious consequences, especially in extreme terrain. 

    (2/10/2026)

    Small wet loose avalanches and rollerballs on a middle elevation southeast aspect

    Photo: Arden Feldman

Avalanche Discussion

It will be a beautiful day in the mountains today with mostly sunny skies and light winds. The forecast area received 6-18” of new snow on Monday - a welcome sight! However, don't let the nice weather and new snow lull you into complacency. With a fresh slab above a variety of weak layers, conditions have become more dangerous in the backcountry. 

There is a high degree of spatial variability and uncertainty surrounding the buried weak layers. We know that surface hoar, near surface facets, and crust facet layers were all buried by the recent snowfall. Buried surface hoar is a particularly tricky persistent weak layer. It can be very difficult to predict which slopes it exists on. Just because it’s not on one slope doesn't mean it isn’t on a similar slope nearby. Additionally, you might not find it at the top of a slope, but it could still exist partway down the slope. The near surface facets and crust facet layers add even more variability to the equation. So, even if you don’t find buried surface hoar, other weak layers could prove hazardous. The main takeaway here is that conditions are complicated, and careful slope assessment is required in the backcountry right now. If you want to avoid the problems entirely, you can stick to low angle slopes without steep terrain overhead. Unfortunately, these weak layers take time to heal, and we will likely be dealing with them for a while. 

Glide cracks are opening up throughout all zones. Glide cracks are very unpredictable and can fail minutes after the crack opens or months after. Avoid spending time under open glide cracks. Cornices have the potential to break off naturally during periods of warming throughout the spring. Minimize the time you spend underneath overhung cornice on warm days. 

Avalanche education is a lifelong journey built on developing sound judgment, gaining experience, and applying repeatable decision-making systems in the backcountry. Our American Avalanche Association (A3) recognized Level 1, Rescue, and Level 2 courses are offered throughout the winter and help you travel smarter in avalanche terrain. Explore current courses and registration on the Education page. 

Please continue to submit observations and ski and ride safe!

Regioni coperte