Northwest Inland

Several weak layers exist in the snowpack and human-triggered avalanches remain possible. Watch for signs of instability such as whumpfing.

On Thursday a large (size 2.5) naturally triggered wind slab avalanche was reported near Ashman. On Tuesday, a small (size 1) rider-triggered wind slab avalanche was reported in northeast-facing, treeline terrain by Hudson Bay Mountain. Whumpfing has been experienced by backcountry users in the Babines, Grizzly Plateau, and Hudson Bay Mountain recently. The whumpfing has been occurring mainly due to the surface hoar layers described in the snowpack summary.

Recent incremental snowfall has been blown around forming wind slabs on mostly northwest through east-facing slopes at ridgetops. Southerly faces in the alpine are scoured down to the ground or an early-season crust. In most areas, two or more preserved surface hoar layers can be found buried between 35 cm and 80 cm deep. They appear to be most prominent at treeline and below but have been observed in some alpine locations as well.Snowpack depths at treeline are variable across the region with generally deeper amounts (~150cm) in the western part and shallower (~80cm) in the eastern part.The snow surface is likely moist or crusty up to treeline, and below 1100 m there is very little snow.

Friday Night

Cloudy with 2 cm of snow expected, southeasterly winds 10-20 km/h, freezing level up to 1100m, and treeline temperatures falling to -4 °C.

Saturday

Cloudy with 2-5 cm of new snow, southerly winds 20-30 km/h, freezing level of 1400m and treeline temperatures rising to 1 °C.

Sunday

Mostly cloudy with no precipitation, westerly winds 10-25 km/h, high of -4 at treeline.

Monday

Mostly cloudy with a trace of new snow, variable winds 5-10 km/h, freezing level varies between 800m - 400m, and a high of -3 at treeline.

More details can be found in the Mountain Weather Forecast.

• Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
• Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.