Avalanche forecast

Flathead Range & Glacier NP

Flathead Avalanche Center
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Avalanche danger

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

Recent snow and increasing southwest winds will form fresh slabs above 5000 feet. Look for blowing snow, dune-shaped drifts, or textured surface snow as visual clues. You can reduce your risk of triggering a slide by avoiding steep, rocky, wind-affected terrain.

Avalanche problems

  • Wind Slabs

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

    Saturday, observers noted increasing southwest winds, snow transport, and surface cracking in wind-affected slopes. The wind continued overnight, drifting the 8-12 inches of recent low-density surface snow. Thin, fresh slabs are forming on a layer of lower-density snow, adding to the instability. These features will be larger, thicker, and more widespread at upper elevations while only found in the most wind-prone locations at middle elevations. Look for them downwind of ridgelines and saddles and on the sidewalls of gullies. 

    Look for rippled surfaces, hollow-sounding stiff snow, and cracks shooting out from your boards or machine. Blowing snow and cornices point toward the direction of loading. Terrain sheltered from the wind will offer a safer and better riding experience.

    (2/16/2023)

    Blowing snow like this is a tell-tale sign that wind slabs are forming on the leeward sides of ridgelines.

    Photo: md

Avalanche Discussion

As of 5 AM, weather stations report an uptick in southwesterly winds that will redistribute the recent unconsolidated snow. To account for these winds, we’ve transitioned our primary avalanche problem from Storm Slab to Wind Slab. Above 6500 feet, the snow available for transport will develop larger and more widespread slabs, while middle elevations will likely have less snow and wind, making for more isolated hazards. 

We dropped our Loose Dry problem today, however keep in mind that fast-running sluffs in steep terrain can still catch you off guard.  Before committing to a steep line, consider the terrain below you and the consequences of taking a ride into places you don’t want to go.

Observers from Saturday reported 3 to 12 inches of cohesionless snow over a stout and supportable crust formed in early February. Varying depths across the region favored upper elevations, and many observations described sluff management as their primary hazard. On steep slopes, observers were challenged by sluffing and sliding on the slick crust. For one party in the northern Whitefish Range, a rider was caught and carried 75 feet, but was thankfully not buried and escaped uninjured. Other observers in the southern Whitefish Range (Example 1, Example 2, Example 3) confirmed a loose, dry problem that was straightforward to manage.

In the Skyland area, riders reported isolated cracking, wind gusts transporting snow, and warming southern aspects from solar input. This contrasted conditions in the Swan Range, where skies were mostly cloudy, and skiers and riders reported powder turns above 5200 feet. As we enter the workweek, the avalanche danger is expected to rise due to new snow overnight, with accumulations estimated to be 6 to 8 inches or more in favored locations.

Upcoming event: Flathead Avalanche Friends Fest, February 21-24. Beacons & Brews, Name That Tune/Name That Avalanche, Workshop Night, Hot Dog Days, and Ultimate Après.  Check out 4 days of events: flatheadavalanche.org/event/friendsfest

Regions covered