Avalanche Forecast
Regions: Bull, East Purcell, Purcells, St. Mary.
Avoid steep, rocky, wind affected terrain where triggering persistent slab avalanches is most likely.
Small avalanches in motion may trigger these deeper layers.
Confidence
Moderate
Avalanche Summary
On Monday, a naturally triggered size 3 persistent slab was reported on a east facing alpine bowl near Panorama.
On Sunday, a skier remotely triggered a size 2 persistent slab avalanche from 50 m away. The avalanche failed on a wind loaded slope on a northerly aspect at treeline near Panorama. The weak layer was 40-150cm deep.
Snowpack Summary
30 - 50 cm of recent storm snow overlies a crust on sunny slopes and lower elevations, and surface hoar or facets on sheltered and shady upper elevations. Southwesterly wind formed slabs on lee features at treeline and above.
Several persistent weak layers consisting of a crust, facets or surface hoar from February and January remain a concern. They are down 50 to 100 cm in most areas.
The bottom of the snowpack is composed of large facets in most areas.
Weather Summary
Tuesday Night
Clear skies, 5 to 10 km/h southwest ridgetop winds, treeline temperature -10 °C, freezing level valley bottom.
Wednesday
Mostly sunny, 5 to 10 km/h southwest ridgetop winds, treeline temperature -4 °C, freezing level 1500 m.
Thursday
Mix of sun and cloud, 10 to 20 km/h southwest ridgetop winds, treeline temperature -3 °C, freezing level 1600 m.
Friday
Mostly cloudy with isolated flurries, 3-5 cm snow, 20 to 30 km/h southwest ridgetop winds, treeline temperature -3 °C, freezing level 1600 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Be aware of the potential for large, destructive avalanches due to deeply buried weak layers.
- Even brief periods of direct sun could produce natural avalanches.
- Avoid steep, sun-exposed slopes when the air temperature is warm or when solar radiation is strong.
Avalanche Problems
Persistent Slabs
Triggering is most likely in wind affected terrain on northerly and easterly aspects. Small avalanches in motion may trigger these deeper layers creating very large and destructive avalanches.
Aspects: North, North East, East, West, North West.
Elevations: All elevations.
Likelihood: Possible - Likely
Expected Size: 2 - 3
Wind Slabs
30-50 cm of recent snow and southwest wind formed wind slabs on lee slopes at treeline and above
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2
Loose Wet
Wet loose avalanches will become very likely when the sun comes out. Avoid overhead hazard from steep sunny slopes when the solar radiation is strong.
Aspects: East, South East, South, South West, West.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1 - 1.5