Purcells

The message remains the same – a complex, and generally weak snowpack is best managed by sticking to lower angled, low consequence terrain. Large persistent slab or deep persistent slab avalanches are reported every two or three days.

Over the past week there have been continual reports of large persistent and deep persistent slab avalanches across the Purcells.

The most recent reports include a remotely triggered size 2 avalanche near Invermere on Friday, that occurred on a north aspect at 2400 m. The avalanche started on a 30 cm deep surface hoar layer and stepped down to the deep persistent weak layer. Another size 2 remote-triggered avalanche occurred on a southeast aspect at 2250 m near Golden. On Thursday, several very large persistent slab avalanches were observed west of Kimberley, including some that were remotely triggered by skiers.

Smaller size 1 to 2 wind slab avalanches have also been reported in alpine terrain over the past few days.

20 to 60 cm of snow since late January is gradually settling and in open terrain has been redistributed by west and southwest wind. A weak layer of surface hoar, facets and crusts is buried beneath that snow, and has become reactive in the southern and western parts of the Purcells where it is more deeply buried (e.g., along Kootenay Lake and the St. Mary drainage). A layer from late November is found 75 to 150 cm deep throughout the Purcells and is part of a generally weak, faceted lower snowpack. Snowpack depths range between 90 and 200 cm at treeline, with the shallowest depths found on the eastern edge of the Purcells.

Saturday night

Partly cloudy, no precipitation, 30 to 40 km/h west wind, treeline temperatures drop to -10 ºC.

Sunday

Sunny periods in the morning then increasing cloud in the afternoon, isolated flurries with trace amounts of snow, 40 to 50 km/h southwest wind, treeline temperatures to -5 °C with freezing level climbing to 1200 m.

Flurries with 5 to 10 cm of new snow, 40 to 60 km/h southwest wind, treeline temperatures reach -3 °C.

Mix of sun and cloud, no significant precipitation, 20 km/h north wind, treeline temperatures drop to -10 °C.

More details can be found in the Mountain Weather Forecast.

• It's critical to stay disciplined and choose only well supported, low consequence lines.
• Use careful route-finding and stick to moderate slope angles with low consequences.
• Avoid rock outcroppings, convexities, and anywhere the snowpack is thin and/or variable.
• Avoid steep convex slopes.
• Be especially cautious as you transition into wind affected terrain.