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

Nov 17th, 2018–Nov 18th, 2018

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

Regions

Glacier.

People, and the sun shining on the slopes above you, are major factors to be watching for today. And please, PLEASE, look out for rocks and other hazards just below the snow surface. It is still mid-November!

Weather Forecast

Clear, cold, and calm. Freezing levels will remain at valley bottom today, light ridge-top winds, and sunny skies. The clear skies will allow plenty of sun to hit southerly slopes. On Sunday, winds will continue to remain light, freezing levels will rise to 1300m, and cloud cover should increase. No snow is forecasted until mid-week.

Snowpack Summary

45cm of storm snow overlies surface hoar or a suncrust that has been found above 1900m up Connaught drainage and in the Asulkan hut area. Deeper in the snowpack is the October melt freeze crust. Snow depths vary from 75cm at Rogers Pass, to 150-170cm in alpine areas.

Avalanche Summary

Numerous sz 2-3 slab avalanches from N and S alpine aspects on Macdonald and Tupper were observed. These ran during the height of the storm on Nov 15th, with several reaching the valley.

Confidence

Due to the number of field observations

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.