Avalanche Forecast
Issued: Apr 21st, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
bchristie,
Avalanche Canada
Check for signs of windslab instability in steep terrain at higher elevations, especially around ridgetops. Shooting cracks or fresh avalanches are signs that you should retreat to terrain that is not exposed to the wind.
Summary
Confidence
Moderate
Avalanche Summary
A few small (size 1) dry loose avalanches were observed out of steep, rocky terrain on Friday.
A few small (size 1) wet loose avalanches were observed out of steep and rocky terrain on Wednesday. Riders also triggered some small (size 1) wind slabs on Tuesday.
Looking forward, wind slabs could be triggered by riders in lee terrain features from Thursday night's storm, and continued moderate southwest wind.
Use plenty of caution along alpine ridges, where cornices may be large.
Snowpack Summary
10-15 cm of snow fell Thursday night. Moderate southwest wind during the storm and continuing through Saturday will keep building wind slabs in lee terrain features. This recent snow sits over a melt-freeze crust on sun-exposed slopes or 5 to 10 cm of dry snow that overlies a thick and hard crust on shaded aspects.
Rising freezing levels on Saturday mean that the surface snow could get dense and moist at treeline and below.
The remainder of the snowpack is strong with varying hard snow layers and bonded melt-freeze crusts. Cornices are large along many alpine ridges.
Weather Summary
Friday Night
Cloudy. Trace of snow expected. Snow/rain line around 1000 m. Treeline temperature around -5 °C. Light to moderate southwest ridgetop wind.
Saturday
Cloudy. No new snow expected. Freezing level rising to 1700 m. Treeline high around 0°C. Light to moderate southwest ridgetop wind.
Sunday
Cloudy. Moderate rainfall, 5-10 mm. Snow/rain line falling from 2000 to 1500 m. Light to moderate southwest ridgetop wind.
Monday
Cloudy. Light snow/rain expected. Snow/rain line rising from 1000 to 1500 m. Light variable ridgetop wind.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Carefully evaluate steep lines for wind slabs.
- Use ridges or ribs to avoid areas of wind loaded snow.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Wind Slabs
Recent snow from Thursday night continues to be redistributed by moderate southwest wind. Assess for slab development before committing to large terrain features.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 22nd, 2023 4:00PM
