Avalanche Forecast

Archived

Apr 5th, 2025–Apr 8th, 2025

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.

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.

There is forecasted to be a spike in the freezing level on Sunday increasing to 2600-2800m. Start and end your day early. Sun plus the warm temperatures will lead to an increase in natural activity particularly if cornices fail acting as gargantuan triggers.

Confidence

Moderate

Avalanche Summary

Size 2 and 3 avalanches have been observed consistently the last few days. It is becoming difficult to determine what is new and old. Some avalanches are being triggered by cornice failures, sun, or loose wet slides that trigger deeper layers. Expect this pattern to continue.

Snowpack Summary

There is 10-35 cm of soft snow overlying a crust on all but due north aspects. 1-5mm Surface hoar sits on top of this crust in many areas. A 50-100 cm settled 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

Sunday will be a mix of sun and cloud, 2 °C, and 2500m or higher freezing level. Expect Monday will bring clouds, flurries, -2 to 2 °C, and 2200m freezing level. Tuesday will be clouds and sun, slightly cooler temperatures, and 1900m freezing level. Wednesday will be similar conditions to Tuesday.

Terrain and Travel Advice

Make conservative terrain choices and avoid overhead hazard.
Even brief periods of direct sun could produce natural avalanches.

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.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.