Avalanche Forecast
Issued: Apr 4th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Cornices and Loose Wet.
mconlan,
Avalanche Canada
Wind slabs may linger up high. Use caution during the heat of the day as cornices and the recent snow warm up.
Summary
Confidence
High - Confidence is due to a stable weather pattern with little change expected.
Weather Forecast
SUNDAY NIGHT: Clear skies, 20 km/h north wind, alpine temperature -5 C.
MONDAY: Clear skies, 10 km/h northwest wind, alpine temperature -2 C, freezing level rising to 1800 m.
TUESDAY: Mix of sun and cloud, 10 km/h southwest wind, alpine temperature -3 C, freezing level 1600 m.
WEDNESDAY: Cloudy with snowfall, accumulation 10 to 20 cm, 20 km/h southwest wind, alpine temperature -8 C.
Avalanche Summary
A natural avalanche cycle was observed in the region on Saturday during the storm. On Sunday, this MIN describes triggering a small wind slab but in large terrain. Looking forward, wind slabs could still be triggered by riders at high elevations and a warming trend has the potential to increase avalanche activity as the snowpack weakens.
Snowpack Summary
Saturday's storm brought around 20 cm of snow to the region above 1600 m. The snow fell with strong southeast wind, so wind slabs may linger high elevations on lee terrain features. The snow overlies a hard melt-freeze crust everywhere except for north aspects above 1600 m, where it sits on previously dry snow. The snow surface may have already melted and frozen into a crust on sun-exposed aspects. Warm air and sunny skies will likely moisten the snow on Monday, particularly on sun-exposed slopes.
Cornices are large and looming along ridgelines. Their release is unpredictable, requiring a large berth if you're travelling above or below them.
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Make observations and assess conditions continually as you travel.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
- Avoid sun exposed slopes, especially if snow surface is moist or wet.
Problems
Wind Slabs
Wind slabs could be triggered by riders in steep, lee terrain features at high elevations from Saturday's snow and strong southeast wind. Carefully assess for slab properties and the bond of the snow to the underlying snowpack prior to committing yourself to consequential avalanche terrain.
Aspects: North, North East, South West, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Cornices
Cornices are large and looming along many ridgelines, and have likely grown with the recent snow and wind. They become increasingly weak when the sun comes out and freezing levels rise. They require a large berth when travelling above and below them.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Loose Wet
A warming trend will likely weaken the snow surface, particularly on sun-exposed slopes midday. The most likely areas to get into trouble would be on steep slopes above terrain traps.
Aspects: South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 5th, 2021 4:00PM
