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

Feb 19th, 2021–Feb 20th, 2021

Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Widespread avalanches certain.
Treeline
Widespread avalanches certain.
Below Treeline
Widespread avalanches certain.

Regions

Glacier.

Conditions are complex and changing. New snow buries windslabs and may be a hazard itself where it slabs up or runs loose dry over the drought interface

Weather Forecast

A westerly 'zonal' flow is setting up over BC bringing flurries today for Rogers Pass followed by a series of fronts Saturday and Sunday. 5cm today with moderate SW winds and a high of -10. 10cm more snow tomorrow with similar moderate SW wind. Heavy snowfall, rising temperatures and strong to extreme W winds on Sunday.

Snowpack Summary

20cm of snow in the last few days covers the cold weakened drought surface. Facets, wind effect and crusts lie under the new snow and make a poor interface for it to bond to. Surface hoar, crusts and facets have still been found down 70-100cm on the January 24th persistent interface. The mid and lower snowpack remain strong.

Avalanche Summary

New snow is building up on a weak interface. Several loose dry avalanches were reported yesterday, running on the drought interface. Recent reports indicates that slabs are still triggerable in isolated areas under the new snow.

Confidence

Forecast snowfall amounts are uncertain

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.