Avalanche forecast

Swan Range

Flathead Avalanche Center
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Avalanche danger

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

Rising temperatures will increase the avalanche danger. Rollerballs or pinwheels are precursors of a Wet Loose avalanche problem. Although Wet Loose avalanches can be easy to identify and avoid, natural avalanches may become large enough to injure a human. Move to shadier aspects or to lower angled slopes if you see signs of wet avalanche activity. 

Avalanche problems

  • Loose Wet

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

    Warm temperatures and clear skies will wet the snow surface and cause it to slide. South-facing terrain that is steep and rocky are typically the first to show signs of warming. The simplest advice is to move to less steep terrain once you observe rollerballs or small sluffs. You can also move to shadier aspects, though keep in mind the sun angle is high this time of year and north-facing slopes also receive solar radiation. Today may be hot enough to cause those slopes to slide as well. 

    (3/31/2024)

    This pile of wet loose debris originated over 1000 feet above in the upper-elevation band. New snow warmed and slid on 3.29 or 3.30. This pile is the result of two or more slides merging. 

    Photo: Mark Dundas

  • Cornices

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

    Today's hot weather put Cornice Fall back on the menue. Be cautious and observant while walking on and near exposed ridgelines. Give the edge of ridgelines a wide berth and use vegetation or rocks as visual landmarks for safe travel. Avoid traveling directly below ridgelines with large cornices.

    (3/11/2024)

    Warm temperatures and solar radiation may cause cornices to fail naturally. Give terrain directly below a wide margin for error. 

    Photo: Cam Johnson

Avalanche Discussion

The past few days of intermittent sunny skies with cold nights have eased the transition into wet snow avalanche problems. Southerly aspects received a couple of melt/freeze cycles, which will slow the onset of natural avalanche activity today and provide a window for safer travel. 

Freezing levels will climb to roughly 8,000 feet today and possibly upwards of 10,000 feet tomorrow with sunny skies. Natural avalanche activity will occur as the day progresses, but should be relatively easy to manage and avoid. 

Timing is your friend today and tomorrow. An early start and exit will be the safest approach to both days. Here are a couple of tips to help plan your day during diurnal melt/freeze cycles.

  • Plan your route to avoid exiting on or beneath avalanche-prone terrain during the afternoon heat. Terrain that faces south and west will be most likely to avalanche. Strategically planning your route can reduce the chances of being forced to cross beneath a slope that is ripe for avalanching. 
  • Plan your day to be up and down before the snow surface becomes wet and gloppy. If you run out of time and feel your feet or machine sinking into wet snow, then it is time to accept defeat and stay off steep slopes.

Regions covered