The best way to manage a complex snowpack like the one in this region is to stick to smaller, low consequence terrain. Don't let your guard down as large persistent and deep persistent slab avalanches are still being reported every two or three days.
Wind slab avalanches are possible to trigger in lee terrain after recent snow has been redistributed by southwest wind. The bond of this snow to underlying layers is suspect.
Large avalanches have been triggered on a 40 to 80 cm deep layer of surface hoar and facets that was buried in late January. This problem seems most concerning in the western and southern Purcells, where the layer is more deeply buried and primed for human triggering. Steep open slopes should be avoided.
It remains possible for riders to trigger a weak layer of facets near the base of the snowpack. The most likely area to trigger it is in shallow areas with variable snow depths. Avoid thin and rocky start zones and select routes that avoid travelling through or under large avalanche paths.
A number of new natural wind slab and storm slab avalanches up to size 2 were reported from the Purcells in the last 48hrs.
Also of note from last weekend.
On Saturday, skiers at Quartz Creek remotely-triggered a size 3 avalanche on a northwest-facing alpine slope at 2300 m. It failed on a 40 to 80 cm deep weak layer.
On Friday, skiers near Invermere remotely-triggered a size 2 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.
15-40 cm of of recent storm snow has been variably distributed by winds and is settling above a layer of surface hoar, facets, and/or crust. This layer has become reactive in the southern and western parts of the Purcells, where it is more deeply buried.
The lower snowpack contains a widespread layer of large, weak facets that is typically 80 to 150 cm deep. Snowpack depths at treeline range between 80 and 200 cm, with the shallowest depths found on the eastern edge of the Purcells.
Tuesday night
Mostly clear. Winds from the west and southwest 10 km/h. Temperature -12˚C in the alpine.
Wednesday
A mix of sun and clouds. No precipitation. Winds from the southwest 20 km/h. Temperature -12˚C to -5˚C.
ThursdayA mix of sun and clouds. Possible flurries in the afternoon. Winds from the southwest 10 km/h. Temperature -14˚C in the morning rising to -7˚C in the afternoon.
FridayCloudy. Flurries delivering up to 7 cm of new snow. Winds from the southwest 10 km/h. Temperature -8˚C.
More details can be found in the Mountain Weather Forecast.
