Avalanche Forecast

Moderate - Uncertainty is due to unpredictable avalanche behavior.

FRIDAY NIGHT: Mostly cloudy with some light flurries and trace accumulations, moderate wind with strong gusts from the west, alpine temperatures drop to -10 C.

SATURDAY: Increasing cloud with afternoon flurries bringing 5-10 cm of new snow, moderate wind with strong gusts from the west, alpine high temperatures around -6 C.

SUNDAY: 5-10 cm of snow overnight then clearing in the afternoon, light wind from the northwest, alpine high temperatures around -6 C.

MONDAY: Mix of sun and cloud, light wind from the west, alpine high temperatures around -8 C.

A few natural size 2 avalanches were reported on east facing wind-loaded slopes on Friday. A few small (size 1) wind slabs have been human triggered at treeline and alpine elevations over the past few days.

A large avalanche was reported at Quartz Creek on Wednesday. The avalanche was triggered by a snowmobile on a convex roll at treeline. The crown of the avalanche was 150 cm thick, but it is uncertain whether the avalanche was a thick wind slab or ran on a persistent weak layer. On Monday, two deep persistent avalanches (size 2.5 and 3) were triggered with explosives in the central part of the region, both running on north aspects in the alpine. These isolated large avalanches highlight the the importance of careful snowpack and terrain evaluation in the Purcells.

20-50 cm of low density snow has fallen over the past week and has shown some reactivity at higher elevations where it has been redistributed it into wind slabs. This snow sits above a rain crust that extends up to 1600-1900 m. Sun crusts can be found near the surface on steep south-facing slopes. The middle of the snowpack is generally settled but the base of the snowpack contains basal facets. It remains possible to trigger these deep weak layers in shallow rocky start zones or from a heavy trigger such as a cornice fall. 

• Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
• Conditions may have improved, but be mindful that deep instabilities are still present.
• Avoid shallow, rocky areas where the snowpack transitions from thick to thin.