Avalanche Forecast

On Friday, size 1-2 wind slab avalanches were triggered by riders and failed naturally, these were reported on northeast-east aspects above 2000 m. Riders also triggered a few persistent slab avalanches size 1-2, with crowns 50 cm deep and failing on surface hoar.

On Thursday, wind slab avalanches up to size 2 were reported occurring on all aspects above 2000 m. Basal facets continued to demonstrate reactivity with two large (size 2) natural deep persistent avalanches reported and explosives triggering a size 3 deep persistent avalanche, all occurring between 2000-2500 m.

On Monday, a fatal skier-triggered avalanche incident occurred in the Selkirk range near Revelstoke. The avalanche occurred on an east aspect at 1900 m, on a steep, open and unsupported slope. The size 2 avalanche had a crown depth of 50 cm and failed on surface hoar buried in early January.

High-consequence avalanche activity has been ongoing for several weeks. Your best defence is to stay diligent in choosing low-consequence terrain. Stick to slopes that have been heavily trafficked throughout the winter and avoid venturing into untouched zones. Stay disciplined and adjust your expectation for this winter.

15-40 cm recent snowfall over the last week and covered a layer of surface hoar and thin crust on solar aspects at treeline and higher, and a supportive crust up to 1700 m around Revelstoke and increasing to 2000 m travelling south through the region. North and westerly winds have redistributed loose snow to lee terrain.

Two layers of surface hoar which formed in early January are found 40-90 cm deep. These persistent weak layers have recently been reactive to human triggering, but snowpack tests are starting to indicate less propagation propensity. Deeper in the snowpack are two surface hoar/facet layers that were active earlier in the season, but recent snowpack observations suggest they are strengthening. The bottom of the snowpack is made up of large weak facets buried in late November, causing the Deep Persistent Slab problem for this region.

Saturday night

Clear and with gusty ridgetop winds. Ridge wind northwest 20-40 km/hr. Alpine temperature -24 C.

Sunday

Sunny in the morning with increasing clouds throughout the day. Ridge wind northwest 10-20 km/hr. Alpine temperature -22 C.

Sun and increasing cloud. Ridge wind southwest 15-30 km/hr. Alpine temperature rising to -16 C.

Flurries, 5-10 cm. Increasing southwest ridge wind 30-40 km/hr. Alpine temperatures rising to -12 C.

More details can be found in the Mountain Weather Forecast.

• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Be mindful that deep instabilities are still present and have produced recent large avalanches.
• Approach lee and cross-loaded slopes with caution.
• Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.