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

Mar 7th, 2020–Mar 8th, 2020

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, 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

Banff Yoho Kootenay.

Avalanche Control is planned for Mt Whymper, the Sunshine Village access road, Mt Field and Mt Stephen Sunday March 8.

No activities in these areas please.

Weather Forecast

Winds dropped of last night but snow - pushing in from the prairies - continues to fall Saturday with another 5cm expected overnight. The formation of a ridge Sunday should push out a few remaining flurries and usher in some clearing for Monday. Light to moderate winds are expected in the alpine until Tuesday when and increase has been forecast.

Snowpack Summary

50-70 cm has fallen in the past week with strong Westerly winds. Expect to find wind slabs in lee areas and exposed terrain features. The recent snow is piling up and buries sun crust on steep solar aspects and the Feb 1 crust in isolated areas up to 1900m. In thin snow pack areas a dense mid-pack sits over a weak, faceted base.

Avalanche Summary

Reports of two deep persistent slab avalanches on Thursday in the alpine from South to East aspects; a sz 3 triggered by cornice fall and a sz 2.5 from explosive avalanche control.

A further report of an explosive controlled sz 2.5 on deep persistent layers on Saturday. We suspect a limited natural cycle is ongoing.

Confidence

Due to the number of field observations

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.

Loose Dry

Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.

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.