Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Dec 22nd, 2025–Dec 23rd, 2025

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.

Regions

East Purcell, St. Mary.

Conditions will change with elevation and wind exposure. Reactive slabs remain a concern in wind-loaded features, but sheltered terrain holds great riding conditions.

Confidence

Moderate

  • Uncertainty is due to the limited number of field observations.
  • Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.

Avalanche Summary

No new avalanches were observed on Sunday. If you are travelling in the mountains, please submit any observations or photos to the Mountain Information Network.

On Friday near Invermere, an explosive triggered a size 1.5 persistent slab on a north-facing treeline slope, failing on a crust 80–110 cm deep. Over the weekend several rider triggered wind slabs were reported up to size 1.5 on north facing slopes.

Snowpack Summary

Around 10 cm of fresh snow is expected by Tuesday morning. This falls over 30-50 cm of wind affected, settling snow that is generally bonding well to the crust below, which is present up to approximately 2100 m.

A thick mid-November crust is buried 70–110 cm deep in eastern terrain, and up to 180 cm in areas with a deeper snowpack. In most areas, faceted grains overlie the crust. Specific, sheltered terrain features have surface hoar present on or near the crust.

Depth hoar (large, weak crystals) are present at the base of the snowpack.

Weather Summary

Monday Night
Mostly cloudy. 5 to 15 cm of snow. 40 km/h southwest ridgetop wind. Treeline temperature -6 °C. Freezing level 1000 m.

Tuesday
Mostly cloudy. 1 cm of snow. 20 km/h southwest ridgetop wind. Treeline temperature -6 °C. Freezing level 1200 m.

Wednesday
Mostly cloudy. 15 to 20 cm of snow. 30 km/h south ridgetop wind. Treeline temperature -4 °C. Freezing level 600 m.

Thursday
Mix of sun and clouds. 3 to 4 cm of snow. 20 km/h southwest ridgetop wind. Treeline temperature -4 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
  • Be careful with wind-loaded pockets, especially near ridge crests and rollovers.
  • Be mindful that deep instabilities are still present in the snowpack.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.