Avalanche Forecast

Monday night: Partly cloudy, moderate west winds, alpine temperatures around -13 C.

Tuesday: Increasing cloud, scattered flurries bringing up to 5 cm of new snow, winds shift to the southwest and increase to strong, alpine high temperatures around -7 C.

Wednesday: Mix of sun and cloud, isolated flurries with trace accumulations, light west winds, alpine high temperatures around -12 C.

Thursday: Mix of sun and cloud, light northeast winds, alpine high temperatures around -14 C. 

Strong winds on Tuesday are expected to continue to build slabs that may be possible to human trigger in leeward features. On Sunday, observers reported human-triggered avalanches in wind-stiffened snow in the south of the region (check out the MIN reports here and here). Cornices may be reaching their breaking point and can act as triggers on slopes below. 

On Saturday, professional operators reported a small (size 1) avalanche releasing 40 cm deep on the Jan 11th surface hoar layer. Observers south of Valemount also reported reactivity on the surface hoar buried down 45 cm. They saw both shooting cracks and slab activity at 1700m on an easterly aspect. 

Since field observations in this region are limited, please consider submitting your observations to the Mountain Information Network. 

Recent snow accumulations ranging from 10-25 cm are being redistributed by variable winds. Winds switched direction from the southwest to the northwest, creating a tricky reverse wind-loading pattern at upper elevations. Winds are forecast to shift back to the southwest and to increase on Tuesday, keeping wind slabs on lee features as a primary concern. Ongoing snow and wind over the past week have contributed to notable cornice growth. 

40-60 cm of snow from the past week has buried a weak of layer of surface hoar that has shown reactivity in snowpack tests. This persistent weak layer is most suspect in sheltered, open slopes at and below treeline.

A couple of older persistent weak layers exist in the mid to lower snowpack. The distribution of these layers is variable, but they follow a similar pattern to the layer discussed above. The upper layer from late December, down about 70-120 cm, consists of spotty surface hoar at shaded treeline and below treeline elevations. The lower layer from early December buried 150 cm deep consists of a combination of decomposing surface hoar with a crust and faceted snow. This layer is most prevalent in areas near Valemount. Observations from adjacent regions suggest that these layers are trending to unreactive.

• Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
• Be aware of highly variable recent wind loading patterns.
• Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.
• If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
• Avoid exposure to slopes that have cornices overhead.