Avalanche Forecast
Issued: Mar 20th, 2024 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs, Loose Wet and Cornices.
ejones,
Avalanche Canada
Rain & new snow do not improve challenging conditions.
Choose mellow terrain until we find a thick, supportive surface crust.
Summary
Confidence
Avalanche Summary
Large wet avalanches, some failing at the ground, were reported throughout the region on Tuesday.
A widespread natural avalanche cycle up to size 3 continued on Monday, with persistent slab avalanches being the most common. A few remote-triggered avalanches were also reported.
Large natural avalanche activity is expected to continue until the temperature drops enough for a hard surface crust to start forming.
Snowpack Summary
Expect to find 5 to 15 cm of snow overlying a melt-freeze crust at higher elevations. Up to 15 mm of rain will fall on already moist snow surfaces up to 1500 m.
Two layers of surface hoar and sun crust can be found in the top meter of the snowpack.
A hard widespread crust formed in early February is buried about 80 to 150 cm deep. This crust has a layer of facets above it, producing the previous large, natural avalanche cycle.
The snowpack below this crust is generally not concerning except in shallow alpine terrain.
Weather Summary
Wednesday Night
Cloudy with up to 10 mm falling as snow above 1500 m, greatest amounts north of Revelstoke. 20 km/h northwest ridgetop winds. Treeline temperature around 0 °C. Freezing level drops to 1700 m.
Thursday
Cloudy with up to 5 mm, falling as snow above 1000 m. 20 km/h northwest ridgetop winds. Treeline temperature around -1 °C. Freezing level drops to 1500 m.
Friday
Few clouds. 10 km/h west ridgetop winds. Treeline temperature around -2 °C.
Spring diurnal cycle begins, freezing levels dropping to surface overnight and rising to about 1500 m during the day.
Saturday
Cloudy. 10 km/h northeast ridgetop winds. Treeline temperature around -2 °C. Spring diurnal continues.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
- Avoid areas with overhead hazard, especially solar aspects.
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
Problems
Persistent Slabs
Two reactive layers exist in the upper snowpack. One is down 40 cm and the deeper one down 80 to 150 cm. We expect natural avalanches on these layers to continue while warm weather continues.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Rain-on-snow may produce wet loose avalanches, especially on steep slopes facing the sun. These may step down and trigger deeper slab avalanches.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Cornices
Cornices are becoming weak with above-freezing temperatures in the alpine. Cornice failure could trigger very large destructive avalanches. Avoid exposure to slopes that have cornices overhead.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Mar 21st, 2024 4:00PM
