Avalanche Forecast

Archived

Mar 28th, 2025–Mar 30th, 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 and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural and human triggered avalanches likely.

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.

10cm of snow is forecast for Saturday with moderate SW winds. If snow amount are more than anticipated, we may see the avalanche danger return to high. Treat the snowpack as suspect at this time and continue to be very conservative in your terrain choice avoiding any bigger terrain that hasn't slid in this latest cycle.

Confidence

Low

Avalanche Summary

No new natural avalanches were observed or reported on Friday.

Snowpack Summary

Temperatures cooled on Friday which has helped the snowpack settle and strengthen (albeit only slightly). 5-10cm of new snow fell what is now overlying the March 28th melt freeze layer that is found on all aspects up tp 2400m (treeline) and all other aspects except true north to ridgetop.

The upper snowpack settled rapidly last week in the warmer temperatures triggering a widespread avalanche cycle on with many slides failing do the basal facet/depth hoar layers. As temperatures cool, it will become harder to trigger these deeper layers but the weak interface still exists and can be triggered by light loads such as a skier. New windslabs are also developing in alpine terrain with the new snow and moderate south west winds

The danger is dropping as the Natural cycle decreases but human triggered avalanches remain likely and we encourage skiers to stick to conservative terrain

Weather Summary

10-20cm of new snow is forecast over the next 24 hours with light-moderate westerly winds and a day time high around -1C and a freezing level forecast to be 1800m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
Avoid exposure to overhead avalanche terrain; avalanches may run surprisingly far.
Keep in mind that human triggering may persist as natural avalanches taper off.

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.