Avalanche Forecast

Archived

Mar 3rd, 2024–Mar 4th, 2024

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

The natural avalanche cycle has started to taper off. That means the snowpack is 100% primed for human triggering. Be very suspect of any slope that has not avalanched and make very conservative decisions for the following days as the snowpack has time to adjust and heal. People are reporting excellent skiing. Equal amounts of people are reporting large whumpfs and close calls with avalanches. The Canmore hill remains closed while snow removal crews work tirelessly to get the roads safe for travel once again.

A Special Public Avalanche Warning is in effect. Click the red SPAW link for details.

Confidence

High

Avalanche Summary

Thanks again for great Min reports! found: Here.

Sunday KMR was able to get out and complete an avalanche control mission. East end of Mt. Rundle performed well and debris hit the Canmore hill burying the road up to 5 meters deep and 20 meters wide.

Mt. Buller also ran full path several times and was impressive propagation in the large open alpine and treeline features.

On the flight, pretty good visibility showed continued evidence of a wide spread avalanche cycle on all aspects running far.

Snowpack Summary

60-90cm of recent snow is now overlying the Feb 3rd crust complex. Storm slabs and wind slabs can be expected in this new snow which will be easy to trigger with a skiers weight. A weak layer of faceted crystals also exists above and below this crust that has been producing moderate sheers. This new snow is beginning to overload this layer and cause a natural avalanche cycle. The November basal facets are alive and well and back on our radar as the February 2 rain crust is deteriorating and not locking in the weaknesses below as it once did. Skier weight has now been able to break through the Feb 2 rain crust in some places, which means that the basal facets can now be more easily affected.

Weather Summary

Monday:

Mainly cloudy with isolated flurries 3-5cm.

Day time high -13 with light West winds

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
Avoid all avalanche terrain during periods of strong wind.

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.

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.

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.