Avalanche Forecast

Archived

Mar 7th, 2023–Mar 8th, 2023

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 possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

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.

Good skiing can still be found in sheltered areas. Generally a weak snowpack, approach all larger features with caution.

Confidence

Moderate

Avalanche Summary

One size 1.5 avalanche that was triggered by a cornice was seen in the Burstall Pass area. Keep in mind that there have been several large natural avlanches in the area within the last 3 days.

Snowpack Summary

The forecasting crew were out in the Burstall Pass area and found good skiing in sheltered areas in the trees. Wind slabs were recently producing easy sheers within the top 25cm. The lower half of the snowpack is made up of facets and depth hoar and on average can be found up to 50-70cm thick from the ground up. The interface with the top of this facet layer and the November surface hoar layer are still producing moderate to hard test results which are planar in nature. These weaknesses will persist for the rest of the season. Forecasters have been avoiding all large open planar slopes at tree line and above.

Weather Summary

Wednesday will be another day of sun and cloud. The morning will be chilly at around -22c and warm up to -10c. winds are expected to be light from East.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be aware of the potential for surprisingly large avalanches due to deeply buried weak layers.
Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

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.

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.