Avalanche Forecast

Moderate - Uncertainty is due to the fact that deep persistent slabs are particularly difficult to forecast.

An Arctic ridge of high pressure brings cold and dry conditions to the region for the next few days.

Sunday Overnight: Partly cloudy, light to moderate S winds, treeline temperature around -16 °C.

Monday: Mainly sunny, moderate E winds, treeline high around -16 °C. 

Tuesday: A mix of sun and cloud, moderate variable winds, treeline high around -20 °C. 

Wednesday: A mix of sun and cloud, light to moderate SW winds, treeline high around -18 °C. 

On Saturday, natural size 2-3 slab avalanches were reported in the far SW corner of the region. These were typically 30-50 cm thick and occurring on NW aspects. In the far north of the region, explosives triggered a size 2.5 persistent slab avalanche which was 30-75 cm thick and released on a weak layer near the ground. This MIN from the Hankin on Saturday has some great photos of natural avalanche activity above the cabin. 

On Monday, wind slab problems are expected to be the primary concern in the region. Older wind slabs are mostly likely found on north and east aspects but as the wind switches direction on Monday, new wind slabs are expected to form on south and west aspects. A lingering deep persistent problem still exists in the region but appears to be gaining strength. This deep weakness is likely creating a low probability/high consequence scenario.

The region picked up 10 to 20 cm of new snow Friday afternoon into Saturday afternoon, with a bit of wind out of the south. Previous to this, the region has been pounded by winds which have formed reactive slabs in wind exposed terrain. New wind slab formation is expected on Monday as winds switch direction and begin to blow from the NE-E. 

Below 1400 m, a thin rain crust exists below the past week's storm snow. There have been reports of faceting around this crust with previous cold temperatures. A spotty surface hoar layer has also been reported down around 100cm in the alpine and treeline. 

An early season crust can be found near the base of the snowpack. It has shown reactivity in the past week with large loads (explosives and cornices), creating large avalanches. We don't know how widespread this problem may be, but we are definitely keeping an eye on it, and would be avoiding large features and areas with thin to thick snowpack transitions.

Snowpack depth at treeline typically ranges from 150-200 cm, with higher values in the western part of the region and tapering to the east.

• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Avalanche hazard may have improved, but be mindful that deep instabilities are still present.
• Avoid shallow, rocky areas where the snowpack transitions from thick to thin.