Avalanche forecast

Swan Range

Flathead Avalanche Center
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Avalanche danger

Sat
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
1 · Low
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Out of date — this forecast expired 5 months ago. You’re viewing past conditions, not the current bulletin.

Highlights

Avalanches remain likely today near and above 6000 feet in new and wind-drifted snow. Expect slides large enough to bury or injure a rider across the terrain, with deeper and more dangerous avalanches on wind-loaded slopes. Safer travel and great snow can be found on low-angle, sheltered slopes well away from ridgelines.

Avalanche problems

  • Storm Slabs

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

    The Swan Range picked up a huge load in a short period of time. Avalanches may fail within the storm snow or at the old/new snow interface. In sheltered terrain near 6000 feet, sensitive slabs will be up to two feet thick, increasing to three feet and deeper at higher elevations. These slabs are large enough to bury or injure a rider on their own, with wind forming thicker, harder slabs three to five feet deep near exposed ridgelines—not a bear worth poking today.

    Assess sensitivity with quick hand pits down to the most recent crust and by testing small, safe slopes (with a spotter). Shooting cracks from your feet or machine are clear signs of unstable slabs—expect similar conditions on nearby slopes. With good visibility today, look for textured, chalky surfaces, rounded pillows of snow, and blowing snow—signs of wind drifting and more slopes to avoid.

    While unlikely, a wind slab could step down to a deeper weak layer (see Problem 2), producing a larger and more destructive avalanche. 

    Loose Snow Avalanches

    Sluffs will be an issue today, especially on sunlit slopes. Expect both natural and human-triggered releases. Most will be small, but some may entrain enough snow to gain mass and speed—don’t let one knock you off your feet above a terrain trap.

    This image from a previous season shows the crown of an unintentional skier-triggered avalanche in new snow. These are the types of slides that can be triggered in both sheltered and wind-affected areas today. 

    Photo: Flathead Avalanche Center

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    2–3

    The January Drought Layer still lurks deep in the snowpack on some upper-elevation, shaded slopes. The good news is that multiple crusts and thick slabs sit above it, making human-triggering unlikely. You’ll likely need to be above 6,500–7,000 feet to even find where it remains a concern. If it does release today, it would most likely be triggered by a new snow avalanche stepping down.

    With plenty of great riding available elsewhere on the mountain, there’s little reason to roll the dice today with this low-probability, high-consequence problem. I recommend staying clear of steep slopes near and above 7000 feet on northwest–northeast–southeast aspects while the dust settles after the big storm. By keeping off of slopes harboring fresh wind slabs today, you’ll also be avoiding this deeper issue.

    (3/17/2026)

    This avalanche failed on a buried weak layer and was triggered by a smaller surface slide. The crown depth is impressive, and the potential size of slides triggered today. Photo: Michael Reavis

Avalanche Discussion

That’s the Noisy Basin special I’ve been hearing about all season. Over 20" of snow and 4.5" of SWE in just over 24 hours is a massive load, with periods of intense snowfall that may have led to poor bonding within the storm snow. Warm temperatures today should help that settle, but they still need to prove themselves. Before our late March warmup, this kind of load would have produced widespread activity on the JDL. We don’t expect that now, but it wouldn’t be surprising to hear about a few large avalanches in the Swan Range.

Elsewhere, the storm was more modest. Snow came in a bit warmer than hoped, but there may be a few inches of lower-density snow on top of a supportable base. The Flathead Range holds more big terrain above 7000 feet, where deeper, more sensitive slabs are likely in exposed areas—that’s the main driver behind the higher danger there compared to the Whitefish Range.

If you’re after steep powder, mature forest could offer good options. Keep an eye out for lingering soft slabs that could push you into trees. As the sun comes out, west aspects may ski well early before warming degrades the snow quality. If you head high onto north-facing slopes, be diligent assessing for wind slabs—this is your most likely way to trigger something deeper.

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This week—our last week of daily forecasts for the 2025–26 winter—we’re highlighting people, teams, and organizations that have contributed notably to Flathead Avalanche’s work and products, and supported the forecast team through a challenging and, hopefully, unusual winter.

National Weather Service Missoula (NWS Missoula):

All the snowpack insight in the world wouldn’t mean much without a reliable weather forecast for the next day. The team at NWS Missoula provides the daily products, tools, consultations, and briefings that form the backbone of our morning mountain weather forecast. A hearty thank you to Joe Messina, the entire Missoula office, and the fine folks across the country who make the NWS Avalanche Weather Program possible.

Flathead Nordic Backcountry Patrol (FNBP):

The FNBP is a committed group of volunteers who show up when it matters most, helping get people out of the mountains when things go wrong. Beyond rescue, they support the avalanche center and the broader community by providing beacon checkers at popular trailheads, partnering with FOFAC for Hot Dog Days, and helping with avalanche education. We, along with the entire backcountry community, are grateful for all that they do.

Avalanche Canada (AvCan):

AvCan allows us to benefit from the heavy lift they’ve done over many years to develop and operate the SNOWPACK model dashboard. We use this tool throughout the season to support our avalanche forecasting. Thanks to Simon Horton and the AvCan team for their continued support.

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