Lawinenlagebericht

Swan Range

Flathead Avalanche Center
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Lawinengefahr

Thu
Hochgebirge
3 · Erheblich
Waldgrenze
3 · Erheblich
Unterhalb
1 · Gering
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Kernpunkte

Warm temperatures and rain to about 6000 feet will increase the avalanche danger. We’ve received reports of four large, remotely triggered avalanches this week. Stick to low-angle terrain that’s not under steep start zones. Slopes big and small are producing destructive avalanches.

Lawinenprobleme

  • Persistent Slabs

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Likely
    Größe
    2–3

    There are two weak layers buried in the upper snowpack. The most troublesome weak layer is buried at a depth of 2 to 4 feet. While snowpack tests are beginning to show mixed results of unstable and stable, avalanche activity continues to warn us that weak layers can’t be trusted.

    In the last week, we’ve received reports of three remotely triggered avalanches in the Whitefish and Flathead Ranges, and one natural avalanche near Spotted Bear. These avalanches all failed on easterly facing slopes between 6000 and 7000 feet. A couple of them were large enough to snap mature trees.

    The only way to manage this problem is to avoid it. And not just avoid the slope itself, but also the runout below. Avalanches have pulled back onto lower-angle slopes, so give ridgelines and the edges of paths plenty of room to avoid being surprised.

    (3/2/2026)

    Crown of a very large (D3) hard slab avalanche that was remotely triggered on Snowshed Mountain. 

    Photo: Michael Reavis

  • Loose Wet

    • Hochgebirge
    • Waldgrenze
    • Unterhalb der Waldgrenze
    Wahrscheinlichkeit
    Likely
    Größe
    1–2

    Today’s storm will start warm, bringing rain to roughly 6000 feet. Rain on snow will cause a round of loose wet avalanches. This may favor northerly-facing terrain, where the snow surface has been protected from recent wind and sun. Loose wet avalanches may grow large enough to bury and injure a person. The bigger concern for this rain event is whether rain-on-snow or a loose wet avalanche triggers a much larger, persistent slab avalanche.

    Plan a foolproof route in and out today. The avalanche danger should diminish once you get above the rain line, although you will still be dealing with a dangerous snowpack. Roller balls or pinwheels are signs that the snow surface is wet and ripe for avalanching. Loose wet avalanches often run through trees and mature timber. Rely on slope angle and not on vegetation for identifying avalanche terrain.

    A photo from earlier in the season of dirty, wet debris in Rescue Creek. These slides may be similar to what we see today on northerly facing slopes. 

    Photo: Josh Lipkowitz

Avalanche Discussion

Travel advice today is about as simple as it gets: avoid avalanche terrain, especially on slopes that face northwest to east to south. This includes small slopes that may be sparsely treed, or big, obvious avalanche paths. Recent avalanches are failing anywhere from 1 to 6 feet deep, and most are unsurvivable. That makes decision-making today easy.

Uncertainty is growing as rain begins to fall. We are pretty confident that we will see loose wet avalanches below the rain/snow line. South and west-facing slopes have been thoroughly worked over by sun and wind, so we expect minimal avalanche activity on those slopes. Slopes shaded from the sun hold dry snow that will be ripe for avalanching if rain falls. The uncertainty lies in whether we will see another round of natural persistent slab avalanches. These may occur below the rain/snow line. A small loose wet avalanche will be a perfect trigger for a larger, persistent slab avalanche. Expect the loose wet avalanche problem to go away quickly once the rain turns to snow.

New snow avalanche problems may develop overnight as more snow falls. Pay attention to snow accumulations and put plenty of space between you and steep slopes. Signs of cracking around your board or machine indicate a slab avalanche problem.

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