Avalanche forecast

Flathead Range & Glacier NP

Flathead Avalanche Center
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Avalanche danger

Fri
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
Out of date — this forecast expired 8 months ago. You’re viewing past conditions, not the current bulletin.

Highlights

Dangerous avalanche conditions still exist on isolated slopes due to strong winds and recent heavy snowfall. You could trigger a slab 2+ feet thick in the new snow. Avoid rollovers and wind-affected slopes, while sticking to more planar, sheltered terrain. Sluffs in very steep terrain can entrain large amounts of snow. 

Avalanche problems

  • Storm Slabs

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

    Copious amounts of snow (16+ inches) fell in the last 48 hours. Dry, cohesionless snow will blanket areas sheltered from the wind. Areas directly below ridgelines and on leeward slopes are likely to have recently formed slabs of wind-drifted snow. As these slabs increase in stiffness, they may also become more sensitive. 

    The recent snow may have buried a weak layer of surface hoar or facets. Any avalanche released today could step down and propagate much wider than expected.

    Seek out planar slopes that are sheltered from the wind. It’s been a while since we’ve had storm totals this deep. 

    A photo from 2022 highlights how storm slabs may break above you. Steer around steep convexities and enjoy the soft snow while it is here.

    Photo: Mark Dundas

  • Loose Dry

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Areas sheltered from the wind have plenty of recent snow, making them prone to natural or human-caused loose-snow avalanches. Ride slopes one at a time and always maintain visual contact with your partner. 

    While generally not large, any sluff that starts today could entrain large amounts of snow due to the recent storm. Atypical snowfall amounts require more attention to what is below you. Being carried into a small depression, over a cliff, or into timber could be exacerbated with deep cohesionless snow, such as we have right now.

    A sluff that starts small can entrain large amounts of snow.  The 16+ inches that the Flathead/GNP received provides plenty of soft, cohesionless snow.

    Photo: Pete Costain

Avalanche Discussion

Anyone who was in the mountains yesterday likely enjoyed a wonderful day of powder skiing or riding. The Flathead and Glacier Park regions received over 16 inches of snow. Winds were light to moderate; however, much of the area remained sheltered, with minimal wind effects.

The Whitefish and Swan ranges still had a powder day but were slightly more wind-affected and received less snow (3-6 inches).

As the initial new snow danger begins to decrease, I’m left with a few thoughts.

  • A recently reported avalanche in the southern Whitefish Range exemplifies the need for caution around buried weak layers. The distribution and sensitivity of these are still uncertain. Reports are coming in, mostly from the Whitefish Range, of folks finding a weak layer associated with the Jan 2 warming event and the Christmas crust. The Swan range seems to have a potential for weakness on the Christmas crust. And the Flathead Range is pretty quiet. I expect this is related to limited access due to low-elevation bushwhacking and, thus, a lack of observations overall.
  • As snow accumulates and more areas open up for recreation, it is hard to temper the stoke. Continue to practice safe travel skills. Only put one rider on a slope at a time. Keep your partner in sight. Dig in the snow to look for weak layers. And practice with your rescue equipment.

Regions covered