Avalanche Forecast
Issued: Apr 6th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Cornices.
ldreier,
Avalanche Canada
The south of the region is expecting up to 40 cm snow by the end of the day Thursday, combined with strong southwest wind. Storm and wind slabs will be reactive to human triggers.
Summary
Confidence
Moderate - Uncertainty is due to the track & intensity of the incoming weather system.
Weather Forecast
Wednesday night: Cloudy, 10-20 cm snow, most snow will fall in the south of the region, strong southwest wind, alpine low -4 °C, freezing level around 700 m.Â
Thursday: Cloudy, 15-25 cm snow, most snow will fall in the south of the region, strong southwest wind, alpine high -2 °C, freezing level at 1100 m.
Friday: Mix of sun and cloud, 10-20 cm snow in the south of the region, moderate west wind, alpine high -3 °C, freezing level at 1000 m.
Saturday: Mix of sun and cloud, up to 5 cm snow, moderate west wind, alpine high -6 °C, freezing level at 700 m.
Avalanche Summary
Many small dry loose avalanches were reported on Tuesday. A cornice failed naturally and entrained snow on the slope below, resulting in a size 2.5 avalanche.
Intense wind loading triggered some very large (up to size 3.5) wind slabs in the Bear Pass area that were reported on Monday morning.
A size 1 storm slab 40 cm deep was skier triggered on a steep roll at treeline on Monday. Warming was reported as the contributing factor that made the slab more sensitive to triggering.
Snowpack Summary
The new snow will add to 30-60 cm recent snow which overlies a hard melt-freeze crust.
Recent moderate to strong winds from varied directions exposed the crust in some areas and formed wind slabs on a variety of aspects.
Around 100 cm down, a layer of weak snow (facets or surface hoar) has been occasionally reported in sheltered areas. The distribution of this layer has been reported as isolated and is likely not a problem in many areas.
Cornices are very large and exposure to them should be minimized, especially during warm or windy weather.
Terrain and Travel
- Watch for fresh storm slabs building throughout the day.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Keep in mind the crust offers an excellent bed surface for avalanches.
- Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
Problems
Storm Slabs
The storm might bring a total of 20-40 cm by the end of the day on Thursday combined with strong southwest wind. Most of the snow will fall in the very south of the region around Terrace and Kitimat. Storm and wind slabs will build throughout the day and will be reactive to human triggers.
At lower elevations, the precipitation might fall as rain and weaken the snowpack resulting in wet loose avalanches.
The northern part of the region will likely see less than 15 cm of snow. The strong southwest wind will form fresh wind slabs in lee terrain features in the alpine and at treeline. Recent winds from varied directions formed wind slabs on a variety of aspects which may still be reactive to human triggers. Use ridges or ribs to avoid areas of wind-loaded snow.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
New snow and wind will add additional load to the already large cornices and might lead to cornice failures. Minimize overhead hazard and give cornices a wide berth when travelling on ridgetops.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 7th, 2022 4:00PM
