Snowfall warning issued for Jasper for late Tuesday evening into Wednesday afternoon. Danger rating will increase if it arrives, low confidence. 15cm or more snow with winds in a short time may cause direct action avalanches on specific slopes.
Weather Forecast
A snowfall warning has been issued for Jasper National Park. A low pressure system moving into central BC will spread cloud and snow into the mountain parks late Tuesday evening. 15cm or more of snow with winds is expected by Wednesday afternoon .
Snowpack Summary
In the Icefields, winds are whipping up what little snow is available. A thin windskin has capped a 2cm layer of small surface hoar and surface facets. Watch this layer as a concern later. A relatively hard mid-pack is providing bridging strength over weak basal facets at tree line and above. Below treeline it is supportive mid-pack where 70cm HS.
Avalanche Summary
No new avalanches reported for several days.
Confidence
Timing, track, or intensity of incoming weather system is uncertain on Wednesday
Problems
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.