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

Dec 1st, 2020–Dec 2nd, 2020

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.
Below Treeline
Natural avalanches unlikely.

Regions

Little Yoho.

Climbers/skiers take note - the upper elevation temperatures rise to +5C tonight & Wednesday causing a bump up in hazard. We expect increased avalanche activity, particularly on steep solar aspects.

Weather Forecast

Tonight a temperature inversion establishes with temperatures at 2000 m and above rising to +5C tonight and through tomorrow. The rise in temperature together with sunny skis will cause existing layers to become more sensitive to triggering or produce natural avalanches on Wednesday. Temperatures will cool Thursday late afternoon.

Snowpack Summary

Variable surface conditions exist with hard wind slabs in exposed locations and softer snow in more sheltered areas. The Nov 5 facet/crust combo is down 50-80 cm and producing variable test results, but can be 'sudden' in character. This crust extends up to 2500 m on N aspects and higher on solar aspects. Snow depths at treeline are 70-130 cm.

Avalanche Summary

No avalanche activity reported Tuesday. There have been a few isolated larger avalanches in the last week on deeper layers including a size 2.5 avalanche on the W aspect of Dolomite Peak on Sunday in a cross loaded gully feature and a couple deep avalanches on steep glacier features. Warm air aloft & sunny skies Wed may cause activity to increase.

Confidence

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.

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.