Avalanche Forecast

Archived

Mar 27th, 2025–Mar 28th, 2025

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Regions

Jasper, Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Maligne, Marmot, Miette Lake, Pyramid.

The snowpack is still recovering from a warming event this week. Surface instabilities remain likely to trigger, and have a high potential to step down resulting in large, dangerous avalanches.

Make conservative terrain decisions, and avoid overhead hazard.

Confidence

Moderate

Avalanche Summary

Road patrols on the icefields Parkway Wednesday observed a widespread wet loose cycle to size 2 in steep terrain on all aspects, triggering persistent and deep persistent slab avalanches in some areas to size 3. Storm slab avalanches were also observed occurring on solar aspects.

New wet loose and slab avalanches continue to be observed, especially at tree line, along the Icefields Parkway through Thursday. Poor visibility into terrain above 2000m.

Snowpack Summary

10-20 cm of new snow is settling quickly. Warm temperatures on Wednesday have resulted in moist surface snow to 2600m. At 2200m the top 80cm remains moist despite cooling temperatures. At treeline and below, the 70-90 cm from earlier in March has settled into a supportive midpack. This bridges a complicated and reactive deep persistent weakness. Where the snowpack is shallow, the bridging is not strong and triggering a large avalanche is very possible.

Weather Summary

Friday

Cloudy with scattered flurries. Accumulation: 4 cm. Alpine temperature: High -2 °C. Ridge wind light to 20 km/h. Freezing level: 2000 metres.

Saturday

Flurries. Accumulation: 7 cm. Alpine temperature: Low -8 °C, High -4 °C. Ridge wind south: 10-25 km/h. Freezing level: 1800 metres.

Sunday

Cloudy with sunny periods and isolated flurries. Precipitation: Trace. Alpine temperature: Low -7 °C, High -2 °C. Ridge wind light to 20 km/h. Freezing level: 1800 metres.

Terrain and Travel Advice

Make conservative terrain choices and avoid overhead hazard.
Remote triggering is a concern; avoid terrain where triggering overhead slopes is possible.

Problems

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.