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

As winter returns this afternoon, you may be able to trigger a small avalanche in fresh, wind-drifted snow. Small slides at the snowpack surface can step down into deeply buried weak layers and quickly become large and destructive. As snow and wind ramp up, give steep, shaded slopes above 6500 feet a wide margin.

If the storm comes on earlier or heavier than anticipated, expect an increase in avalanche danger before day’s end.

Avalanche problems

  • Wind Slabs

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

    Gusty southwest winds will build slabs this afternoon, drifting new snow downwind of ridges, saddles, gully walls, and mid-slope features. Existing cornices are a good indicator of where fresh slabs are likely to form. Expect them to grow in size and sensitivity as the storm progresses.

    Wind slabs are most reactive during and just after formation—while you’re traveling this afternoon. Some slabs may sit on a slick crust and run fast and far. In favored areas, avalanches could become large enough to bury or injure a rider by day’s end. 

    If you find 6-8 inches or more of new/drifted snow, take notice. Shooting cracks and/or blowing snow signal wind slab avalanches are possible nearby. The same upper-elevation shaded slopes that harbor a deeply buried weak layer are the most likely places to develop sensitive wind slabs today (see Problem 2).

    (2/26/2026)

    Blowing snow will signal active wind slab formation today. If you see any, give a buffer to steep slopes nearby.

    Photo: Flathead Avalanche Center

  • Persistent Slabs

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

    The January Drought Layer (JDL) of surface hoar, buried three months ago, remains intact on some upper-elevation slopes that face northwest through northeast to southeast. Recent large avalanches over the past few weeks suggest that it still has some gas in the tank. Without X-Ray Goggles, there’s no reliable way to know if it still exists and is capable of propagating a crack on a given slope. Because of snowpack variability, even snow pits can’t be definitive. 

    While human triggering has become unlikely - we have no reports of rider-triggered avalanches in nearly a month - the layer can still fail naturally during warming or with shock-loads from cornice falls or smaller avalanches that originate in new and drifted snow. The resulting avalanches can break thousands of feet wide and would be unsurvivable. With snow and wind inbound, avoidance remains the only surefire strategy to keep the dragon napping. While we don’t think the layer is intact at mid-elevations, avalanches descending from above make it wise to limit time spent under any steep, leeward slope.

    Triggering is more likely where the weak layer is shallow, such as on rocky or wind-raked slopes. If you can confidently rule out wind or storm slabs, south-facing slopes may offer some nice powder riding in the new snow without the risk of a deeper avalanche on the JDL.

    (3/15/2026)

    A very large, destructive slab avalanche on Running Rabbit Mtn. The depth of the crown is very deep (est. 8ft +). The likelihood is descreasing while the consequence remains severe. 

    Photo: Michael Reavis

Avalanche Discussion

So long, spring. After weeks of warmth and a few days of corn harvesting, new snow avalanches are back on the menu. The first of two weather systems this week will arrive midday, bringing a quick shift in conditions to the mountains. Danger stays Moderate today, but sensitivity rises—you’re more likely to trigger an avalanche this afternoon than you were yesterday.

With the JDL, the forecast team keeps saying, “I wouldn’t be surprised”. If this storm passes with no JDL avalanches, I wouldn’t be surprised. If a large, destructive slide breaks thousands of feet wide and deep, I also wouldn’t be surprised. For me, that uncertainty means trying to find some good powder riding on slopes where we are more confident this thing isn’t an issue: slopes that face south through southwest through west. Or, low-angle shaded slopes without overhead hazard should provide great riding over the next few days as a bit of snow stacks up.     

Yesterday (Saturday), we saw an example of that uncertainty and variability. Snow profiles at 6000 and 6500 feet showed a wetted-out, unthreatening layer, while at 6900 feet on the same slope, we found dry, intact surface hoar 4-5 feet below the surface. That prompted us to steer clear of any steep shaded slope at the upper-elevations. 

Regions covered