Avalanche Forecast
Regions: East Purcell, Purcells.
While avalanches are expected to be small, slabs may step down to deeper weaknesses within the snowpack.
Surface hoar may still be triggerable below the recent snow
Confidence
Moderate
Avalanche Summary
On Monday a natural wind slab was observed from north facing alpine terrain, and dry loose sluffing was observed in wind sheltered areas.
Deep persistent slabs have been reported within the last 3 days, to size 1.5 from explosive and human triggers, on north facing slopes at treeline and below.
Wind slab reactivity is expected to continue, while deep persistent layers remain unpredictable. Observations are limited, please submit a MIN if you head into the backcountry!
Snowpack Summary
10-15 cm of wind affected snow sits on sun crusts on south facing slopes, surface hoar in sheltered areas, and previously wind-affected snow.
In the Invermere area, weak faceted snow at the base of the snowpack has caused several small persistent slab avalanches at the base of the snowpack. So far reports suggest it does not extend throughout the forecast region.
Treeline snow depths are generally 50 to 70 cm, with deeper wind-loaded pockets in the alpine.
Weather Summary
Tuesday Night
Partly cloudy. 10 to 20 km/h west ridgetop wind. Treeline temperature -10 °C.
Wednesday
Partly cloudy with a chance of flurries. 10 to 20 km/h west ridgetop wind. Treeline temperature -6 °C.
Thursday
Mostly clear skies. 10 to 20 km/h southwest ridgetop wind. Treeline temperature -6 °C.
Friday
Mostly clear skies. 10 to 20 km/h southwest ridgetop wind. Treeline temperature -6 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be careful with wind-loaded pockets, especially near ridge crests and rollovers.
- Approach steep and open slopes at and below treeline cautiously, as buried surface hoar may exist.
- Be mindful that deep instabilities are still present in the snowpack.
Avalanche Problems
Wind Slabs
Wind affected snow sits over weak surfaces including surface hoar, which remains rider triggerable. Wind slabs may step down to the weak crystals at the base of the snowpack, producing larger avalanches.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2
Deep Persistent Slabs
Weak faceted snow at the base of the snowpack remains a concern primarily in the Invermere area. Recent activity has occurred on steep, smooth north facing slopes where the snowpack is shallow (thin) and weak.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2