Lawinenlagebericht

Northwest Mountains

Crested Butte Avalanche Center
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Lawinengefahr

Sun
Hochgebirge
2 · Mässig
Waldgrenze
2 · Mässig
Unterhalb
2 · Mässig
Open full map
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Kernpunkte

A decent freeze overnight under a clear sky, will keep the avalanche danger lowest during the morning hours. High temperatures will increase the avalanche danger throughout the day as snow surfaces become wet and slabs soften. High clouds moving in may help keep some snow surfaces cold, and strong winds at upper elevations will greatly reduce wet avalanche concerns in those areas. A trickier problem lurks on northerly aspects with the potential for slabs to break on weak layers in the upper snowpack on some slopes. A notable result was a skier having a near-miss with a persistent slab last Thursday on Mt. Axtell.  Carefully evaluate the snowpack structure and terrain consequences before riding in steep terrain. 

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1–2

    Skiers and riders have triggered a handful of soft slab avalanches that released on buried weak layers in the upper snowpack this week (Example A, Example B, Example C).   Avalanche activity has been most common on the northeast quadrant of the compass, where there are thin crusts surrounding facet layers paired with more favorable wind loading from the last storm. You can also find isolated instabilities on other aspects, particularly on paths that avalanched back in February and have refiled with a new slab. Monitor potential slab thickness and terrain consequences as you move through steep terrain, treating suspect aspects as guilty until snow assessments have proven them innocent.  

    3/18: A skier was caught by surprise by this persistent slab on Mt. Axtell.

  • Loose Wet

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1

    Dozens of small wet loose avalanches have run over the last couple days.  With warm temperatures again today, expect the potental for more natural activity and easily triggered sluffs later in the day on sunbaked slopes.  Wet loose instabilities are easy to recognize and avoid:  If you see rollerballs, pinwheels, or small sluffs starting from rocky terrain features, move towards colder aspects or lower slope angles to avoid the problem. Wet loose avalanches will generally be small, but they can cause trouble if they drag you into rocks, trees, or into a gulley.   If you find your skis or boots seaking deeply into wet sloppy snow, you may have found the conditions for an isolated wet slab avalanche. 

    Recent wet avalanche activity in the East River Valley above Gothic.

Avalanche Discussion

The cloud forecast and winds should help decrease wet avalanche activity today. However, near and below treeline elevations are still going to feel the effects of today's high temperatures. Other than loose wet avalanche concerns, we can't completely rule out an isolated wet slab avalanche. Sinking deeply into a wet sloppy snowpack would be one concerning area for wet slabs that you may find on the southern half of the compass. Though the warm temperatures will also help soften slabs over dry persistent weak layers in areas highlighted by the persistent slab avalanche problem. Yesterday a snowmobiler triggered a full depth avalanche on a NW aspect out by Tincup Pass near Taylor Park. The upper snowpack was wet when this avalanche was triggered. 

The persistent slab avalanche problem is close to being called unlikely in the NW Mountains, but we are not quite there. We have observed more slab avalanche activity than expected since last weekend's storm. You can read about some of this avalanche activity in the most recent weekly snowpack summary, and see the most recent reports in the observations tap. The majority of this activity has been in the northwest mountains that were favored by the last storm. This avalanche problem is more isolated in the SE Mountains and the problem likelihood has dropped a notch for that forecast area.

The avalanche danger trend is currently expected to become LOW at all elevations tomorrow. The main thing driving tomorrow's avalanche danger will be new wind slabs. Winds will be strong overnight with the arrival of the snow, but new snow amounts are expected to be on the low end and not be enough to elevate the overall avalanche danger. The colder temperatures will put an end to wet avalanche issues and further decrease the likelihood of the persistent slab avalanche problem. 

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