Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Jan 13th, 2023–Jan 14th, 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 unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.

Regions

Banff Yoho Kootenay, Banff, East Side 93N, Kootenay, Lake Louise, LLSA, Sunshine, West Side 93N.

While freezing levels remain elevated and winds values continue to transport snow at upper elevations, the forecast team has little confidence in how the deeper instabilities will react to these changes. Although natural avalanche activity has subsided on the deep persistent problem, we still continue to see reports of human triggering.

Confidence

Moderate

Avalanche Summary

No new natural avalanches were observed or reported Friday. lake Louise snow safety produced slab avalanches to size 2 with the use of explosives. These avalanches were failing on reloaded bed surfaces.

Snowpack Summary

Moderate to strong SW winds have created windslab at upper elevations. In protected areas, 10-20 cm of loose snow sits over a denser mid-pack which has formed a slab over the weak facet layers below - this loose snow is getting blown into slabs. The December 17 weak layer is down 25-60 cm and becoming less reactive. The November 16 deep persistent layer of facets and depth hoar is near the base of the snowpack, continuing to show sudden failures.

Weather Summary

Warm temperatures will continue Saturday with freezing levels near 1600m. Light flurries are expected on the Western slopes of the region with trace accumulation throughout the day. Ridgetop winds will begin to weaken Friday evening. More unsettled weather is forecasted for Sunday and the start of the week.

Terrain and Travel Advice

  • Use careful route-finding and stick to moderate slope angles with low consequences.

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.

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.