Avalanche Forecast
Regions: Badshot-Battle, Central Selkirk, Dogtooth, Esplanade, Glacier, Goat, Gold, Jordan, North Columbia, North Selkirk, South Columbia, West Purcell.
Natural and human-triggered avalanches will become very likely to trigger on Thursday.
Confidence
Moderate
Avalanche Summary
Many small to large (size 1 to 3) storm and wind slab avalanches were triggered naturally, by humans, and by explosives on Tuesday. They mostly occurred at treeline and alpine elevations and on all aspects. Most slabs were 40 to 80 cm deep.
With new snow and wind, both natural and human-triggered avalanches will be very likely on Thursday.
Snowpack Summary
Around 20 to 40 cm of snow is forecast by Thursday afternoon with southwest wind. New storm and wind slabs will likely rapidly form. This will add to the 50 cm of storm snow that accumulated since Saturday. All this snow sits on a hard melt-freeze crust and surface hoar crystals in wind-sheltered terrain.
Weak layers of surface hoar and/or faceted grains buried mid-February and late-January are around 60 to 150 cm deep.
The lower half of the snowpack is strong.
Weather Summary
Wednesday Night
Cloudy with 5 to 10 cm of snow. 20 to 30 km/h south ridgetop wind. Treeline temperature -4 °C. Freezing level 1300 m.
Thursday
Cloudy with 10 to 20 cm of snow and local amounts of up to 30 cm possible. 20 to 40 km/h southwest ridgetop wind. Treeline temperature -5 °C. Freezing level 1100 m.
Friday
Mostly cloudy with 2 to 5 cm of snow. 10 to 20 km/h south ridgetop wind. Treeline temperature -7 °C.
Saturday
Cloudy with 5 to 10 cm of snow. 20 to 30 km/h south ridgetop wind. Treeline temperature -5 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Travel in alpine terrain is not recommended.
- Watch for fresh storm slabs building throughout the day.
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Be aware of the potential for large avalanches due to buried weak layers.
- Be especially cautious as you transition into wind-affected terrain.
- Storm slabs in motion may step down to deeply buried weak layers and result in very large avalanches.
- Remote triggering is a concern; avoid terrain where triggering overhead slopes is possible.
Avalanche Problems
Storm Slabs
New snow and strong wind will form new slabs and continue to build touchy slabs from all the storm snow since the weekend. We expect triggering large avalanches to become very likely as snow accumulates. Be wary of any consequential slope.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely - Very Likely
Expected Size: 1.5 - 3
Persistent Slabs
Buried weak layers from January and February could still be triggered, particularly at upper treeline and alpine elevations. Storm slab avalanches could step down to these layers, forming very large avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 3.5