Avalanche Forecast
Regions: South Columbia.
Snow amounts will vary highly throughout the region, with 10-30 cm. Storm slabs will build throughout the day and strong southwest wind will form fresh wind slabs. Choose conservative terrain if you see more than 15 cm new snow and wind is moving snow.
Confidence
Moderate - Uncertainty is due to the track & intensity of the incoming weather system.
Weather Forecast
Sunday night: Cloudy, 5-15 cm snow, moderate to strong southwest wind, alpine low -4 °C, freezing level at 1500 m.
Monday: Cloudy, 5-15 cm snow, moderate to strong southwest wind, alpine high -4 °C, freezing level at 1500 m.Â
Tuesday: Mainly cloudy, 5-10 cm snow, moderate to strong westerly wind, alpine high -5 °C, freezing level at 1500 m.
Wednesday: Sunny, trace of new snow, light to moderate westerly wind, alpine high -3 °C, freezing level at 1700 m.
Avalanche Summary
On Saturday, a few natural dry loose to size 2 and many small wet loose avalanches were reported on steep sun-exposed slopes. Skiers triggered many small storm/wind slabs and dry loose that ran on the recent crust about 10-20 cm deep, as well as a dry loose of size 2. And explosives triggered a small storm slab.
On Friday, small natural wet loose avalanches were observed. Skiers triggered small wind/storm slabs and wet loose avalanches, as well as a large (size 2) wind slab avalanche.Â
On Thursday, a few natural wind slabs up to size 2 were reported from the alpine on northeasterly slopes. Skier triggered dry loose avalanches and small storm slabs were easily triggered within the new storm snow up to size 1.5.Â
Snowpack Summary
The snow surface became moist on sun-exposed slopes up to 2000 m in the last couple of days and formed a crust overnight.Â
The new snow will add to 10-50 cm recent snow that overlies a crust from late March. The amount of snow on the crust tapers rapidly at lower elevations. This crust is present on all aspects up to an elevation of 2600 m. Below the crust, the snow is moist.Â
The upper snowpack consists of multiple crusts that were formed in March and February.
The early-December rain crust is approximately a metre off the ground. Reports have recently indicated that large slab avalanches have failed on this interface earlier last week following a rain and warming event. This layer may be dormant now due to colder weather, however, it may appear again during the next big warm-up or with increased load from wind, snow, and/or rain.Â
Terrain and Travel
- Watch for fresh storm slabs building throughout the day.
- Fresh wind slabs will likely form throughout the day, diligently watch for changing conditions.
- Keep in mind the crust offers an excellent bed surface for avalanches.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Avalanche Problems
Storm Slabs
Storm slabs will build throughout the day. The amount of new snow will be highly variable in the region and can range from 10 to 30 cm by the end of the day on Monday.
Moderate to strong southwest wind will redistribute the new snow and build fresh wind slabs in lee terrain features in the alpine and at treeline.
The slabs will be most reactive to human triggers where they overlie a crust.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1 - 2
Cornices
Springtime cornices are large and unpredictable. New snow and wind will further grow cornices, and the additional load can lead to cornice failures. Give them a wide berth when travelling at ridge crest and avoid overhead exposure.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine.
Likelihood: Likely
Expected Size: 1.5 - 3