Avalanche Forecast

FRIDAY NIGHT: Cloudy, 10-20 cm new snow, strong westerly wind, temperature low -7 C.

SATURDAY: Cloudy, 15-25 cm new snow, extreme southwest wind, temperature high -2 C, freezing level rising to 700 m.

SUNDAY: Cloudy, 20-30 cm new snow and rain at lower elevations, extreme southwest wind, temperature high +1 C, freezing level at 1200 m.

MONDAY: Mostly cloudy, 10-15 cm new snow, strong southwest wind, temperature high -2 C, freezing level at 800 m.

On Friday several small natural and explosives triggered storm slab avalanches up to size 1.5 were reported. A few natural wind slab avalanches up to size 2.5 were observed on steep alpine slopes. 

Whumpfing was reported by a party on Wednesday (see this MIN report). Many natural wind slab avalanches of size 2-2.5 were observed on lee terrain features and cross-loaded slopes. Several small dry and wet loose avalanches were reported on steep solar aspects. Several dry loose avalanches up to size 2.5 on steep terrain were reported on Tuesday. 

Natural wind slabs to size 2 have been reported on various wind loaded and cross loaded aspects over the weekend. These wind slabs were formed by the recent outflow winds. Wind slabs have also been reactive to human triggering with ski cuts in the size 1-1.5 range.

On Saturday explosives control triggered cornice and wind slabs, mostly size 1-2 with the odd larger result with big cornices.

It is worth remembering that skiers were able to trigger unsupported pillows failing on surface hoar down 25-40 cm near Terrace last week. Although there are no recent reports of avalanches failing on this layer, it is still propagating in some snowpack tests and this layer might become reactive with the increasing snow load.

10-30 cm new snow sit on top of a variety of older snow surfaces consisting of surface hoar, facets, crust and hard wind affected layers. In sheltered areas, the cold temperatures promoted surface faceting and formed a 20-40 cm thick facet layer. Below treeline, 20-50 cm of soft snow sits above isolated pockets of surface hoar and a crust which is more prominent on solar aspects. The late January interface is down 40-80 cm and consists of surface hoar in sheltered locations, a crust on solar aspects, and facets and stiff wind affected snow at upper elevations. 

The mid-pack seems to be well settled. Deep persistent layers appear to have mostly become unreactive, except for the Bear Pass area and the far reaches south of Kitimat. 

• Storm slab size and sensitivity to triggering will likely increase through the day.
• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
• Pay attention to cornices and give them a wide berth when traveling on or below ridges.