Lawinenlagebericht

Southeast Mountains

Crested Butte Avalanche Center
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Lawinengefahr

Sat
Hochgebirge
2 · Mässig
Waldgrenze
2 · Mässig
Unterhalb
2 · Mässig
Veraltet — dieser Lagebericht ist last year abgelaufen. Du siehst vergangene Verhältnisse, nicht den aktuellen Bericht.

Kernpunkte

Yesterday, a skier triggered a large, tree-snapping avalanche on a cross-drifted slope just north of our forecast area near Marble.  Although the odds of triggering an avalanche like this have decreased since last Tuesday's storm and wind event, the consequences remain the same.  The most dangerous slopes are recently wind-loaded on northerly to east aspects at higher elevations or terrain with variable and shallow snow depths on the north half of the compass.  Slab instabilities are typically thinner and less common in wind-sheltered terrain below treeline.  

Lawinenprobleme

  • Wind Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1–1.5

    Yesterday afternoon and last night, increased westerly winds caused some drifting at higher elevations, forming a fresh generation of shallow wind slabs below corniced ridges or in cross-loaded terrain features.  Monitor for evidence of recent drifting, such as thicker, harder pillows of snow to identify features of concern.  You can avoid wind slabs by traveling in wind-sheltered terrain.  

    A shallow Wind Slab from earlier this week below a leeward ridgeline.  

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Possible
    Größe
    1.5–2.5

    In the past week, we've observed large to very large slab avalanches breaking on weak layers in the upper snowpack and near the ground at higher elevations.  Feedback on the problem will be variable and infrequent. These issues are most concerning on wind-loaded terrain on colder, shadier aspects highlighted by the persistent slab rose.  Avoid steep, wind-loaded slopes and wind-affected terrain with variable snow depths to reduce your risk.   Persistent slab instabilities are more isolated below treeline; stay alert on very steep or unusually shallow slopes. Southerly aspects typically lack the problem.  

Avalanche Discussion

Persistent slab avalanche patterns since the significant wind drifting events earlier this week highlight the most problematic terrain.  Time since loading and rounding within our most active weak layer (March 13th facets) are reducing the number of problematic slopes compared to earlier this week.  The more reliable options for stepping out into steeper alpine terrain are on southerly aspects, where our March weak layers were typically cooked off, and our early season weak layers saw meltwater.  On these sunny aspects, we may see enough solar warming today to cause small wet loose avalanches. These point-release instabilities are easy to recognize and manage.

Although weak layers exist on shady (northerly) aspects below treeline (ex. Brush Creek), the snowpack and avalanche activity have been relatively quiet this week.  If you're riding in steep, wind-sheltered areas with a deep and consistent snowpack, it's worth pausing to evaluate how thick and sensitive the March slab is over small-grained facets buried earlier this month. I suspect any lingering instabilities will be on very steep, unsupported terrain features, breaking 1 to 2 feet deep.   If you're riding in wind-sheltered areas in our shallow zone, keep in mind there is isolated potential for an avalanche to break several feet deep on weak layers near the ground. I'd be most cautious in steep, rocky terrain with variable snow depths.  

New snow and active wind loading will increase the avalanche danger tomorrow, forming new snow instabilities and stressing buried weak layers.  

Events:  Stop by our next trailhead day this Sunday at Kebler TH.  We'll be grilling brats and celebrating the winter season!

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