Avalanche Forecast
Regions: Glacier.
Slab avalanches may still be triggerable on steep planar slopes at higher elevations, especially as the upper snowpack warms with the heat of the day.
Expect to find challenging travel below treeline, with a variety of crusts capping a thinning snowpack.
Confidence
High
Avalanche Summary
Thursday, a field team observed two remotely triggered size 1 storm slabs above the Bonney Moraines on E aspects, failing on the Apr 9th crust.
There were a few large (up to size 2.5) avalanches observed in the highway corridor from steep unsupported terrain in recent days - some of these storm slabs suspected to be failing on the April 9th crust.
Wednesday, a field team on Christiana ridge ski cut a few moist storm slabs on steep solar aspects, sliding on the April 9th crust.
Snowpack Summary
In the Alpine and high Tree-line, 20-30cm of settling snow sits over a firm crust on any slope that catches the sun and well settled dry snow on due north aspects.
At tree line the snow depth is at a record low of around 220cm. The Feb 3rd crust/facet layer persists at upper elevations, buried down 80-140cm.
Below tree line is a well-settled spring snowpack with a strong surface crust that will break down during the heat of the day.
Weather Summary
An improving trend is forecast for the weekend, with a ridge of high pressure briefly setting up over our area.
Tonight: Cloudy periods. Alpine low -2°C, freezing level (FZL) 1400m. Light SW ridgetop winds.
Sat: Mix sun/cloud. Alpine High 2°C, FZL 2400m. Light SW winds.
Sun: Mix sun/cloud. Low 1 °C, High 4 °C, FZL 2500m. Gusty moderate SW wind.
Mon: Flurries (up to 10cm). Low -8 °C, High -1 °C. FZL 1800m. Light W wind.
Terrain and Travel Advice
- Carefully monitor the bond between the new snow and old surface.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
Avalanche Problems
Storm Slabs
The new snow will need time to bond to the old surfaces, especially where it sits over a firm crust. Use extra caution near ridge crests and lee features, where deeper wind deposits will be more reactive. Natural avalanches will be possible on solar aspects when the spring sun shines!
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2.5
Loose Wet
Loose snow avalanches may be triggered by the strong spring sun in steep/rocky terrain.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 1.5