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

Jan 11th, 2026–Jan 12th, 2026

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

Regions

South Rockies, East Purcell, St. Mary, Bull.

New snow and wind are expected to form reactive storm slabs on Monday.

If you see less than 10 cm of new snow, the danger may only be MODERATE.

Confidence

Moderate

  • Forecast snowfall amounts are uncertain.

Avalanche Summary

On Saturday

  • A few small wind slabs were ski cut at treeline and below treeline elevations. They failed on a buried layer of surface hoar.

  • A large (Size 2) naturally-triggered wind slab failed on a north-facing alpine slope.

On Friday

Looking forward

  • We expect storm slabs to become more reactive as snow accumulates on Monday.

Snowpack Summary

10 to 20 cm of new snow on Monday, combined with strong southwesterly winds, will build fresh storm slabs. These slabs are expected to be most reactive in wind-loaded areas

Around 30 to 40 cm of snow currently overlies surface hoar in wind-sheltered terrain, and a sun crust on steep south-facing slopes. The new snow may overload these layers, creating larger-than-expected storm slabs.

A deep persistent weak layer consisting of a thick melt-freeze crust, with weak faceted snow and/or depth hoar, can be found near the ground.

Weather Summary

Sunday Night
Cloudy. 0 to 5 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -4 °C. Freezing level around 1300 m.

Monday
Cloudy. 5 to 15 cm of snow. 40 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level around 1500 m.

Tuesday
Mostly cloudy. 3 to 5 mm of precipitation as snow or rain at treeline. 25 km/h west ridgetop wind. Treeline temperature 1 °C. Freezing level around 2500 m.

Wednesday
Mostly sunny. 30 km/h west ridgetop wind. Treeline temperature 3 °C. Freezing level around 3000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Use increased caution at all elevations. Storm snow is forming touchy slabs.
  • Surface hoar distribution is highly variable. Avoid generalizing your observations.
  • Avoid shallow snowpack areas, rocky outcrops, and steep terrain where triggering is most likely.
  • Avoid freshly wind-loaded terrain features.

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.