Avalanche Forecast

Archived

May 4th, 2024–May 7th, 2024

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

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.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

Be conservative with terrain for the next little while. Recent storm snow will remain a concern until we return to a spring snowpack.

Confidence

Moderate

Avalanche Summary

Numerous recent loose wet / loose dry avalanches up to sz 2.5 on all aspects. Two recent skier accidental avalanches also occurred on north aspects at 2250m failing below the recent storm snow down 75-100cm.

Snowpack Summary

New surface crust today on all but shaded/north aspects above 2200m. Below this 50-75cm of recent storm snow overlies a buried crust. This interface has been reactive to skier traffic, and will remain a concern until conditions return to a spring snowpack. Be patient and conservative with terrain for the next little while.

Weather Summary

Another system is set to hit us Sunday morning, with forecasted precip amounts up to 30cm by Wednesday night. This system is coming in warm, which could mean rain below 2000m. keep an eye on new snow amounts, and how it bonds with the existing surfaces.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

If triggered loose wet avalanches may step down to deeper layers resulting in larger avalanches.
Keep in mind that wet avalanches can be destructive due to their high density.

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.