As freezing levels rise, the likelihood for large cornice failures and wet loose avalanches will increase. Start early and plan to be off large slopes before the heat of the day.
Check out the latest Forecaster's Blog for more information on managing current conditions.
Summary
Confidence
Weather Forecast
THURSDAY NIGHT: Clear / Moderate, northeast ridgetop wind / alpine low temperature -2 / Freezing level 2100 m.
FRIDAY: Sunny / Light, northeast ridgetop wind / alpine high temperature 10 / Freezing level 2700 m.
SATURDAY: Sunny / Light, northwest ridgetop wind / alpine high temperature 11 / Freezing level 2900 m.
SUNDAY: Cloudy with isolated flurries; 3-5 cm. / Moderate, northeast ridgetop wind / alpine high temperature 1 / Freezing level dropping to 1700 m.
Avalanche Summary
Numerous naturally triggered wet loose avalanches up to size 2.5 were reported near Fernie on Tuesday.
As freezing levels continue to rise and remain elevated overnight, the likelihood for large cornice failures and wet loose avalanches will increase. Cornice failures could trigger deeply buried weak layers on steep, rocky slopes with a shallow or thin to thick snowpack.
Snowpack Summary
Lingering wind slabs may still be reactive in isolated locations on steep northerly aspects in the alpine. All other terrain is undergoing a melt-freeze cycle with successive days of warm sunny weather.
Strong solar radiation and warming will likely trigger the large cornices that hang over ridgelines. Cornice falls could trigger large avalanches on the slopes below.
The snowpack is overall strong and settled, although intense warming could potentially weaken deeper layers in steep, rocky terrain with a shallow or thin to thick snowpack.
The snow line is slowly creeping up the mountains, making some access areas snow-free.
Terrain and Travel
- Extra caution is needed around cornices under the current conditions.
- Avoid exposure to slopes that have cornices overhead.
- As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.
- Back off slopes as the surface becomes moist or wet with rising temperatures.
Problems
Cornices
Strong solar radiation and warming will likely trigger the large cornices that hang over ridgelines. Cornice falls could trigger large avalanches on the slopes below.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Loose Wet
Expect natural wet loose avalanches to occur on solar aspects when the sun comes out.
Aspects: East, South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Apr 16th, 2021 4:00PM
