Avalanche forecast

Cooke City

Gallatin NF Avalanche Center
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Avalanche danger

Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Temperatures will rise rapidly today making the snow wet and increasing the likelihood of wet avalanches. Persistent slab avalanches and wind slab avalanches remain a concern, and all three avalanche problems may overlap. It’s complex and dangerous.

Avalanche problems

  • Wet Slabs

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

    There will certainly be some wet loose avalanches, but the greater threat are wet slabs that may occur as buried persistent weak layers become wet.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2.5

  • Wind Slabs

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

Avalanche Discussion

There has been some impressive avalanche activity near Cooke City which had lots of wind and snow combined with buried weak layers this weekend (view those slides HERE). This week we will start adding wet avalanches to the list.

In other places: The Bridger Range had a decent sized wind slab on Saddle on Monday as well as what appears to be a persistent slab avalanche on the west side of Saddle. Yesterday in Beehive Basin near Big Sky, Andrea (intern and PhD student) got collapses on buried surface hoar about 1.5’ deep while collecting field data on wet slabs. Just south of Big Sky yesterday a snowbiker triggered a wind slab about 1’ deep and 70’ wide. 

For today, there are several avalanche problems to contend with. Wind slabs are still a concern but should be stabilizing. Persistent slab avalanches remain a serious threat with multiple, faceted layers buried 1-3 feet deep. With near record breaking heat coming today, wet avalanches are now a major issue. There will certainly be some small wet loose slides, but what worries me is the potential for wet slab avalanches. A good example occurred about two weeks ago in Hyalite Canyon.

Avoiding avalanches today requires considering all these problems - sunny slopes will have wet avalanche issues, shaded slopes will have persistent slab avalanche issues, and there will still be some lingering wind slab issues on wind loaded slopes. These avalanche problems may also overlap in weird ways. The complexity makes it dangerous. 

Today the avalanche danger across the forecast area is CONSIDERABLE because safe travel requires “careful snowpack evaluations, cautious route finding and conservative decision making.” The main change from yesterday is that the likelihood of wet avalanches will be increasing.

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