Avalanche Forecast

No recent avalanches have been reported recently, but whumpfs were noticed Sunday at treeline on a northeast slope near Fraser Peak. This failure layer is suspected to be the buried surface hoar layer that produced some isolated but surprising avalanches last week.

Expect to see increasing avalanche activity with the incoming storm on Wednesday-Thursday.

Before the storm, up to 20 cm of snow covers old, firm, wind-affected or crusty surfaces. Deeper deposits may exist on lee slopes. Pockets of hard wind slabs, that may not bond well to the old surface, still linger in alpine terrain.In isolated areas, buried surface hoar may be found 20 to 40 cm deep. Below 1500 m, a thick melt-freeze crust is buried 50 to 100 cm deep. The mid-pack is generally strong and bridges the weak crystals at the base of the snowpack.

The average snowpack depth at treeline is around 200 cm.

Wednesday Night

Cloudy with 10 to 15 cm expected. 40 to 50 km/h southwest ridgetop wind. Treeline temperatures around -3 °C

Thursday

Cloudy with 10 to 15 cm of new snow expected. 50 to 60 km/h southwest ridgetop wind. Treeline temperatures around 0 °C.

Friday

Cloudy with 10 cm of new snow expected overnight. 30 to 50 km/h south ridgetop wind. Treeline temperatures around -3 °C.

Saturday

Partly cloudy. 30 to 50 km/h south ridgetop wind. Treeline temperatures around +5 °C. Freezing level rising to 2000 m by the end of the day.

More details can be found in the Mountain Weather Forecast.

• Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
• Avoid exposure to overhead avalanche terrain during periods of heavy loading from new snow, wind or rain.
• Back off if you encounter whumpfing, hollow sounds, or shooting cracks.