Avalanche Forecast

Archived

Apr 1st, 2025–Apr 4th, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

Fresh snow has started to fall, which will help refresh the skiing conditions.

There have been significant avalanches in the Park throughout the week, so it's still a good idea to avoid overhead hazard and stick to mellow, supported terrain.

Confidence

Moderate

Avalanche Summary

March 31, Three Size 3 avalanches were reported on the unnamed peak to the NW of Mt. Cirrus. One of the avalanches was reported to have a 3 meter deep crown.

March 30, Two Size 2.5 Deep persistent avalanches were observed on Roche Bonhomme. Field teams observed numerous wet loose avalanches up to size 1 due to increased solar warming. These smaller avalanches were then triggering larger persistent and deep persistent slabs up to size 2.5

Snowpack Summary

5-10cm of new snow overlies a crust on all but northerly aspects. There may be surface hoar on top of this crust in some areas. A 50-100 cm mid-pack rests on top of weak facets. The lower snowpack consists of depth hoar and breaking down crusts. Tree line snow depth is 110-170 cm.

Weather Summary

Wednesday

Mainly cloudy with isolated snowfall.

Precipitation: 5 cm

Alpine temperature: High -5 °C.

Ridge wind northwest: 10-20 km/h.

Freezing level: 1600 metres.

Terrain and Travel Advice

Make conservative terrain choices and avoid overhead hazard.
Even brief periods of direct sun could produce natural avalanches.
Be mindful that deep instabilities are still present in the snowpack.
Loose avalanches may step down to deeper layers, resulting in larger avalanches.
A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.

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.

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.

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.