The Coquihalla is the hot spot for snowfall and avalanche activity right now. Avalanches will become more dangerous as the low density snow starts to consolidate into a cohesive slab.
Confidence
Fair - Track of incoming weather is uncertain on Wednesday
Weather Forecast
A strong northwesterly flow will direct most of the precipitation associated with the incoming storm on Wednesday south of the border, meaning this region will either stay dry or have light snowfall of up to 5 cm. Winds will be light from the west during the day on Wednesday, picking up to moderate to strong overnight. Treeline temperatures will be cold--around -15C. On Thursday, the region should stay mostly dry and cold, although freezing levels may start to rise by the end of the day. On Friday, a punchy frontal system hits the region, bringing heavy snowfall and strong southwesterly winds. Temperatures will rise, with freezing levels climbing to around 500 m.
Avalanche Summary
Natural loose snow avalanches were noted on Tuesday in the Coquihalla. Visibility was poor and no observations were made in the alpine. However, it did not appear that significant slab avalanche activity took place. Skiers triggered slabs up to size 2 in the Coquihalla region on Saturday (incident reports here: https://avalanche.ca/cac/library/incident-report-database/view).
Snowpack Summary
30-80 cm very low density snow has accumulated over the last few days. The Coquihalla and areas around Hope have seen the highest amounts. Winds recently picked up into moderate range from the southwest - just enough to create some soft slabs on lee slopes in exposed areas. Below the storm snow lies a rain crust at lower elevations (up to around 1800 m) and old wind slabs in exposed areas at higher elevations. Weak layers lower in the snowpack have generally ceased to be of concern, except perhaps in thin rocky areas.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.