Avalanche Forecast

Archived

Apr 7th, 2025–Apr 8th, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Regions

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

Start and end your day early. A cooling trend should improve the travel condtions.

Confidence

Moderate

Avalanche Summary

Size 2 and 3 avalanches have been observed consistently through the spring transition. Avalanches are being triggered by cornice failures, sun, and/or loose wet slides that trigger deeper layers.

Snowpack Summary

Moist snowpack treeline and below where spring temperatures are penetrating well into the snowpack on all but north aspects in the alpine and treeline. Near-surface crusts on solar aspects are unsupportive and may have small, preserved surface hoar. A 50-100 cm settled mid-pack rests on top of weak facets, depth hoar, and weak old crusts. Tree line snow depth is 100-150 cm.

Weather Summary

Overnight: Isolated flurries. Low -3 °C. Ridge wind SW: 15-30 km/h.

Tuesday: Cloudy with sunny periods and isolated flurries. High -3 °C. Ridge wind W: 15-35 km/h. Freezing level: 1800 metres.

Wednesday: Cloudy with sunny periods and isolated flurries. Low -5 °C, High -4 °C. Ridge wind SW: 15-25 km/h. Freezing level: 1900 metres.

Terrain and Travel Advice

Make conservative terrain choices and avoid overhead hazard.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

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.

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.