Avalanche Forecast

Archived

Mar 2nd, 2024–Mar 3rd, 2024

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

A natural avalanche cycle is ongoing, with numerous large avalanches being reported and multiple near misses. Avalanche terrain, as well as overhead hazard should be avoided.

Confidence

High

Avalanche Summary

There have been some very close calls from people getting out. One at Crowfoot Glades and one on HWY. 93S. Thanks to those who shared about their incidents, the forecasting team and general public appreciate it!

Additionally, we've seen numerous natural and explosive-triggered avalanches, up to size 3.5 with some avalanches running full path. The potential for large natural avalanches is very real.

Human triggering in avalanche terrain remains likely.

Monday

There have been some very close calls from people getting out. One at Crowfoot Glades and one on HWY. 93S. Thanks to those who shared about their incidents, the forecasting team and general public appreciate it!

Additionally, we've seen numerous natural and explosive-triggered avalanches, up to size 3.5 with some avalanches running full path. The potential for large natural avalanches is very real.

Human triggering in avalanche terrain remains likely.

Tuesday

There have been some very close calls from people getting out. One at Crowfoot Glades and one on HWY. 93S. Thanks to those who shared about their incidents, the forecasting team and general public appreciate it!

Additionally, we've seen numerous natural and explosive-triggered avalanches, up to size 3.5 with some avalanches running full path. The potential for large natural avalanches is very real.

Human triggering in avalanche terrain remains likely.

Snowpack Summary

50-90 cm of new snow fell from Feb 23 to March 2. This combined with strong winds has formed a 40-60 cm storm slab in many exposed areas at alpine and treeline elevations. The Feb 3 facets/crust layer is down 50-90 cm and exists up to 2500m. The base of the snowpack consists of facets and depth hoar. This basal layer is weaker in shallow snowpack areas.

Average snowpack depths at tree line range from 110 cm (to the east) to 170 cm (to the west).

Monday

50-90 cm of new snow fell from Feb 23 to March 2. This combined with strong winds has formed a 40-60 cm storm slab in many exposed areas at alpine and treeline elevations. The Feb 3 facets/crust layer is down 50-90 cm and exists up to 2500m. The base of the snowpack consists of facets and depth hoar. This basal layer is weaker in shallow snowpack areas.

Average snowpack depths at tree line range from 110 cm (to the east) to 170 cm (to the west).

Tuesday

50-90 cm of new snow fell from Feb 23 to March 2. This combined with strong winds has formed a 40-60 cm storm slab in many exposed areas at alpine and treeline elevations. The Feb 3 facets/crust layer is down 50-90 cm and exists up to 2500m. The base of the snowpack consists of facets and depth hoar. This basal layer is weaker in shallow snowpack areas.

Average snowpack depths at tree line range from 110 cm (to the east) to 170 cm (to the west).

Weather Summary

Scattered flurries across the range. Trace accumulations are expected however pay attention to convective snowfall bringing more snow than forecast. Light to moderate westerly ridgetop winds. Freezing levels at valley bottom, with an alpine high of -14C.

Click here for a more detailed weather forecast

Tuesday

Scattered flurries across the range. Trace accumulations are expected however pay attention to convective snowfall bringing more snow than forecast. Light to moderate westerly ridgetop winds. Freezing levels at valley bottom, with an alpine high of -14C.

Click here for a more detailed weather forecast

Terrain and Travel Advice

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.
Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Remote triggering is a big concern, be aware of the potential for wide propagations and large, destructive avalanches at all elevations.

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.

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.

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.