Avalanche Forecast

Archived

Mar 14th, 2023–Mar 15th, 2023

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Little Yoho.

Up to 30 cm has fallen in this region and will take the next 24 hours to settle. Check the bond of the new snow to the previous surface as there as surface hoar, crust and facets buried on March 12. The basal facets in this region are less pronounced then further east (weaker snowpack) and thus we expect the avalanche danger to subside more quickly here over the next several days.

Confidence

Moderate

Avalanche Summary

No new avalanches have been reported in this region, but to the east in the weaker snowpack, a large, deep size 3 on Puzzle Peak crossed the standard uptrack (solar triggered probably). The Lake Louise ski area continues to trigger deep (ground) avalanches from their explosive control work. Finally, a large natural avalanche in Kananaskis Country ran over some ice climbs on Mt. Kidd.

Snowpack Summary

3-day storm totals are Sunshine 15 cm, Simpson, 13 cm, Stanley 11 cm, Bosworth 22 cm and Bow Summit 31 cm.

This new snow has fallen on a freshly buried (March 12) layer of surface hoar, facets and sun crust and in the next few days we will see how well it bonds. Generally, we expect the snowpack to settle well over the next few days as the storm snow finds its place. The basal facets are less pronounced in this region with deeper snowpack and will become less reactive over the next few days.

Weather Summary

A quiet few days of weather ahead as a ridge of high pressure builds over the region keeping skies partly cloudy with no new snow expected and light winds over the next several days. Temperatures will remain cool, with overnight lows hitting -20 in the alpine and daytime highs reaching -5 or warmer in the valley bottoms.

For a more detailed forecast click here.

Terrain and Travel Advice

Uncertainty is best managed through conservative terrain choices at this time.
Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.

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.