Avalanche Forecast
Regions: Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Jasper, Maligne, Marmot, Miette Lake, Pyramid.
The deep persistent problem is still a problem. A weak refreeze Saturday evening along with potential snow or rain on Sunday will continue to destabilize the snowpack.
Watch for isolated wind slabs in the high alpine and thin to thick snowpack areas where triggering the deep persistent slab is more likely.
Confidence
Moderate
Avalanche Summary
Three size 2 deep persistent slab avalanches were observed on Saturday (26th) along the Icefields Parkway, along with numerous wet loose avalanches up to size 2. Northerly aspects in the alpine are also beginning to produce wet loose avalanches up to size 1 on steep terrain features.
Snowpack Summary
In sheltered northerly slopes above 2600m, 5-20 cm of soft snow exists. Isolated wind slabs exist on wind exposed lee slopes in the alpine.
The upper snowpack at treeline and below is a series of crusts. The lower snowpack is dry, faceted, and weak.
High north aspects offer the best spring riding conditions, though the snowpack remains susceptible to triggering deeper, unstable layers.
Weather Summary
Saturday evening freezing levels are due to only drop to 2000m. Forecasts predict snow anywhere from 1mm to 10mm on Sunday. Temperatures are going to be a little cooler with freezing levels up to 2100m and an alpine high of -1°C. Warmer weather will return Monday.
Terrain and Travel Advice
- Back off slopes as the surface becomes moist or wet with rising temperatures.
- Loose avalanches may step down to deeper layers, resulting in larger avalanches.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
- Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
Avalanche Problems
Loose Wet
Even though temperatures will be slightly cooler on Sunday, the sun will still have a significant effect on the snowpack. Plan to travel early and be off steep slopes before the heat of the day.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Wind Slabs
Pockets of wind slab remain in the alpine, primarily in wind-loaded features. While distribution is limited, these slabs could still be reactive in steep, unsupported terrain.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2.5
Deep Persistent Slabs
This is combination of midseason persistent weak layers and the weak facets & depth hoar at the bottom of the snowpack. Field team observed 3 x size 2 deep persistent slab avalanches on Saturday 26th. These were triggered by smaller avalanches, and then stepping down to these weaker layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 4