Avalanche Forecast

Archived

Apr 3rd, 2023–Apr 4th, 2023

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

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

Good skiing continues to be found on North aspects. Two fresher looking avalanches along tent ridge.

Confidence

Moderate

Avalanche Summary

1 fresh crown reported on a Min on tent ridge, a fresh looking size 2 windslab in the tent bowl. Otherwise no new observed or reported.

Snowpack Summary

Roughly 10cm of snow has fallen since Saturday morning. This is settling rapidly. Anything with a hint of solar exposure now has a 3-5cm crust. Valley bottom is still unsupportive underneath the crust. The surface crust extends to at least 2200m and even higher on south and southwest slopes. At about 2000m there's a bit more structure and the snowpack is supportive. This is where the trouble layers start to become more apparent. The weak facet and depth hoar is down about 60-80cm at treeline and the weak basal layers are down about 120-150cm. Today small convective flurries throughout the area, But no real accumulation.

Weather Summary

Tuesday is looking to be mostly cloudy with scattered flurries. Up to 5cm. Day time highs of -9 and 10-20 km Southwest winds.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
Minimize exposure to sun-exposed slopes when the solar radiation is strong.

Problems

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.

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.