Avalanche Forecast
Regions: Little Yoho.
Excellent spring skiing continues with new snow in the forecast for Tuesday. Keep in mind that it is still possible to trigger the deep persistent facets in steep terrain, especially from thin areas or with large triggers such as cornices.
Weather Forecast
Unsettled spring weather could bring as much as 10-15cm of new snow on Tuesday with light SE winds and temperatures remaining cool. Freezing levels are forecast to stay below 1800m. A slight clearing trend and continued cool temperatures is forecast for Wednesday with a few more flurries.
Snowpack Summary
Up to 30cm of snow has fallen in the last several days above 2000m. At lower elevations the snowpack is moist on solar aspects while the upper elevation snow remains cold. There is still some uncertainty surrounding the weaker basal facets in thin snowpack areas of the Little Yoho region with occasional sudden collapse test results in the facets.
Avalanche Summary
A few loose moist avalanches up to size 1.5 were observed out of steep solar alpine terrain on Monday near Lake Louise. Explosive control produced a couple size 1.5-2 slab avalanches in the recent storm snow with minimal propagation. Ski areas reported being able to ski cut small wind slabs from the recent snow up to size 1 that were running far.
Confidence
Intensity of incoming weather systems is uncertain on Tuesday
Avalanche Problems
Persistent Slabs
The snowpack is slowly gaining strength however the basal facets remain a concern in thin snowpack areas and large triggers could create big avalanches on these facets. Use caution in steep terrain and avoid thin snowpack areas when possible.
- Pay attention to overhead hazards like cornices which could trigger the deep persistent slab.
- Choose the deepest and strongest snowpack areas on your run.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 2 - 4
Cornices
April is cornice failure season, and we are getting regular reports of cornices failing and triggering deep slabs. Mature cornices can break much further back than you expect, so give them a wide margin when traveling on ridges.
- Pay attention to overhead hazards like cornices which could trigger slabs.
- Give cornices a wide berth when travelling on or below ridges.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 3
Loose Dry
Another 10-15cm of snow is forecast on Tuesday. If this arrives we expect to see sluffing steep alpine and tree line terrain, and possibly some isolated wind slabs in immediate lee areas of the alpine. Use caution if entering lee loaded areas.
- Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2