Avalanche forecast

Flathead Range & Glacier NP

Flathead Avalanche Center
View on map

Avalanche danger

Sun
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
1 · Low
Open full map
Out of date — this forecast expired 6 months ago. You’re viewing past conditions, not the current bulletin.

Highlights

Riders are likely to trigger a large avalanche on weak layers buried 2 to 4 feet deep. Where recent strong winds have stiffened the snow surface, you may not notice signs of instability, such as cracking or collapsing, until you trigger a slide. Choose low-angle slopes that are not affected by wind or connected to steep terrain for the softest and safest conditions. 

Avalanche problems

  • Persistent Slabs

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

    The most suspect slopes harboring preserved surface hoar and facets occur on NW-NE-S aspects, where numerous human-triggered and natural slides occurred over the past two weeks (image). The widespread weak layers (image) are buried 2-4 feet deep, and triggering an avalanche on them is likely.

    The recent windstorm has stiffened the slab overlying the weak layers in wind-exposed locations. On these slopes, riders may not receive feedback such as collapsing (whumphing), shooting cracks, or remotely triggered slides. The first sign of instability may be the avalanche you trigger.

    On wind-sheltered slopes, the slab is softer and may provide feedback that you found a sensitive slab. In these areas, riders may trigger a slide remotely from flat terrain to the side, below, or above a steep slope.

    The travel advice remains straightforward: Stick to low-angle slopes without overhead hazard while traveling on NW-NE-S aspects. Recent crowns have reached into low slope angles, confirming that riders should remain well back from the edge while on ridgelines or traveling above convexities. 

  • Wind Slabs

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

    Powerful SW winds (image, image) over the past few days have redistributed loose surface snow into stiff slabs on wind-exposed slopes. These features will be a mix of soft and hard slabs and will increase in thickness as you gain elevation. Look for them in the usual spots: downwind of summits, ridgelines, saddles, and on the sidewalls of gullies. Due to the recent impressive wind speeds, you may find them farther downslope than anticipated and in other unusual locations.  

    Blowing snow and fresh cornice growth point toward wind-loaded slopes. A textured surface and dunes are indicative of wind effects. You may experience a drummy sound as you travel over dense wind-drifted snow resting on lower-density snow. Cracking in the snow surface indicates a sensitive soft slab, while hard slabs may not provide any signs of instability until you trigger an avalanche.

    A surface avalanche in wind-drifted snow could step down to a buried weak layer, creating a much larger slide as described in the Persistent Slab problem above. Choose slopes sheltered from the wind for the best snow quality, while being mindful of defaulting to lower-angle terrain on NW-NE-S aspects, where the weak layer has been most reactive.

    The previous few days of powerful winds transported significant snow and stiffened the surface on many wind-exposed slopes.

    (2/26/2026)

    Photo: Guy Zoellner

     

Avalanche Discussion

An impressive southwest wind event that began on Wednesday will taper off this morning. Several days of consistent moderate to strong average wind speeds, with extreme or gale-force gusts (>38 mph), have stiffened the surface on many wind-exposed slopes.  In this terrain, triggering a large, dangerous avalanche on the buried weak layer remains likely, although the strong surface slab can limit the impact of a person’s weight, making it slightly more difficult to trigger. Unfortunately, when a rider finds a thinner or weaker area of the slab, the resulting avalanches will propagate farther, leading to a large to very large avalanche.

There remain plenty of slopes not affected by the wind where a soft surface slab is present, making it easier to trigger avalanches failing on buried weak layers. 

High pressure builds today through Tuesday, bringing warming temperatures and sunshine. This may further strengthen the slab resting on the buried weak layers, especially on slopes facing the sun. 

You may have noticed that the Persistent Slab problem is not listed on the southwest and west aspects. Buried weak snow can be found on these slopes, but we have not recorded any avalanches there over the past few weeks (image). However, digging into the snow to look for the weak layers is recommended if you plan to ride steep terrain on these aspects. 

The anticipated warming conditions will melt the limited amount of loose surface snow, producing small wet sluffs on sun-baked slopes. Due to recent wind scouring and the lack of fresh snowfall, there doesn't appear to be much snow available, so this problem shouldn't be an issue except in extreme terrain where you could be knocked off your feet.

 

Regions covered