Avalanche Forecast

Archived

Apr 5th, 2025–Apr 8th, 2025

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Regions

Kananaskis, Bow Valley, Highwood Pass, North 40, Spray - KLakes.

High Freezing levels and strong solar input is forecast for Sunday. If you head out, be sure to start your trip EARLY and be done early before conditions warm up. Northern aspects are still holding dry snow.

Confidence

Moderate

Avalanche Summary

One recent sz 2 avalanche in the Miners gully area close to Canmore. Teams were out of the field by noon on Saturday and no other avalanches were noted.

Snowpack Summary

Low elevation areas had moist snow by 11am. Most direct solar aspects have a thick temperature crust that carries the weight of a skier. East and west aspects have more of a breakable crust and only pure north aspects have dry snow. The March 28th crust is down 20-50cm and found as high as 2600m. Above this elevation on the northern aspects there is still some uncertainty with regards to the basal layers so continue to be curious at this elevation. Winds increased out of the NW throughout the and some windslab development was noted at upper elevations.

With the strong solar input forecast on Sunday be sure to limit your exposure to solar aspects. Cornices are also failing in the heat at this time of year.

Weather Summary

Temperatures are forecast to warm up on Sunday with daytime highs around +2. Freezing levels are forecast to climb to 3000m with clear skies and strong solar input. Winds are forecast to be light out of the NW.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Avoid shallow snowpack areas, rocky outcrops, and steep terrain where triggering is most likely.
Avoid exposure to overhead hazards when solar radiation is strong.
Limit exposure to steep, sun exposed slopes, especially when the solar radiation is strong.

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.

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.