Avalanche forecast

Flathead Range & Glacier NP

Flathead Avalanche Center
View on map

Avalanche danger

Mon
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
Open full map
Out of date — this forecast expired 8 months ago. You’re viewing past conditions, not the current bulletin.

Highlights

Saturday's light snowfall and breezy conditions produced fresh slabs of wind-drifted snow that may be sensitive to a rider's weight. An etched surface, pillow-shaped drifts, and fresh cornice growth are signs of wind effect. Bypass the dense surface snow for the surprisingly good riding in sheltered locations. 

Avalanche problems

  • Wind Slabs

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

    This past week's incremental snowfall and impressive southwesterly winds built several generations of wind-drifted slabs. The most recently formed slabs may disguise larger, thicker slabs formed over the previous few days. The probability of triggering a slide increases with elevation, as does the resulting size. 

    You will find these features near and below ridgelines, in mid-slope gullies, and behind terrain features such as rock outcroppings and ribs. Cornices and active wind-drifting point toward wind-loaded slopes. Due to unusually strong winds, slabs may be found in areas that are usually sheltered.

    Cracking underfoot or sled indicates you have found a slab, while cracks that shoot away from you confirm the slab is sensitive. If you encounter a dense surface over softer snow, choose a lower-angle slope to increase your safety margin.

    (12/20/2025)

    Cracking in a steep convexity above the tree well. This indicates that the rider found a surface slab. Steep rollovers or convexities amplify the slab's effects.

Avalanche Discussion

This past week's snowfall was overshadowed by severe wind events that caused widespread damage across western Montana, including power outages, downed trees, and the closure of most of the WMR ski area for a day. Continued light snowfall has improved riding conditions, but fresh slabs are still forming on wind-exposed slopes. Some of these slabs are in unusual locations due to recent strong-to-extreme winds. 

Josh and Mike were in the Flathead Range on Saturday, where they noted blowing snow at mid and upper elevations and good riding in sheltered terrain. Their observation warned of the severe blowdown they encountered, which may be the norm for the remainder of this season on access trails. Two parties (Observation, Observation) in the side country of WMR noted cracking underfoot and shooting cracks in the surface snow. Both groups found these conditions in areas usually sheltered from the wind, but may have been affected by this week's unusually strong winds. WMR ski patrol did not have results from ski cutting, but explosives initiated slabs about a foot thick on steep northwest slopes that have not opened to the public this season and resemble a backcountry snowpack. Riders in the upper Red Meadow area reported “fender deep and over the hood” conditions. 

Another round of moisture arrives in the Flathead later today and continues into Monday. Expect fresh wind slab formation with possible storm slabs developing in isolated areas favored by snowfall.

The December solstice (winter solstice) in Kalispell is at 8:03 am on Sunday, December 21, 2025. In terms of daylight, this day is 7 hours, 44 minutes shorter than the June solstice. In most locations north of the equator, the shortest day of the year is around this date.

Regions covered