Avalanche Forecast

Saturday night: Cloudy with flurries bringing 5-10 cm of new snow. Strong to extreme southwest winds.

Sunday: Cloudy with continuing snowfall with another 5-20 cm of new snow. Strong to extreme southwest winds easing over the day. Alpine high temperatures around -8.

Monday: Cloudy with isolated flurries, increasing overnight. Light southwest winds. Alpine high temperatures around -8.

Tuesday: Cloudy with continuing scattered flurries and about 5 more cm of new snow (10 cm with overnight amounts), continuing again overnight. Moderate to strong southwest winds. Alpine high temperatures around -7.

A MIN report from Friday in the Hudson Bay Mountain area does a great job of illustrating the wind slab problem affecting the region in recent days, including some isolated natural activity. Expect this problem to evolve into something a couple of notches more dangerous on Sunday, especially in the west of the region, as forecast snowfall and wind form touchy new surface instabilities. 

On Wednesday, a guide on belay was able to trigger a large (size 2), touchy cornice chunk with a kick at 1650 metres in the Hudson Bay Mountain area. More fragile new cornice growth is expected to form with forecast weather.

An uncertain 10-30 cm of new snow is expected to accumulate in the region over Saturday night and Sunday, favouring the west of the region. Strong to extreme winds will accompany the overnight storm pulse.

The new snow will add to wind affected recent snow (and wind slabs) in exposed areas and to settling storm snow in more sheltered areas. Incrementally increasing totals from last weekend's storm and light snowfall over the week are likely around 20-30 cm near Smithers and closer to 70-100 cm in the southwest of the region. At lower elevations, much of the weekend's precipitation fell as rain, creating crusty surfaces now buried by a bit of low density snow.

Collectively, this new and recent snow overlies hard wind affected snow at alpine elevations, potentially surface hoar crystals on sheltered north aspects, or melt-freeze crust on south aspects and below treeline. Recent observations suggest warm temperatures have aided bonding at this interface.

The mid and lower snowpack is reported as well settled and strong in most areas. However, weak facets exist at the base of the snowpack in the more shallow snowpack zones within much of the region and always have the potential of being triggered on steep, rocky slopes with a shallow or thin to thick snowpack; especially with large loads such as a cornice fall.

• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Storm slab size and sensitivity to triggering will likely increase through the day.
• Make observations and assess conditions continually as you travel.