Avalanche Forecast

Archived

Dec 2nd, 2022–Dec 3rd, 2022

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.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

Jasper, Brazeau, Churchill, Cirrus-Wilson, Fryatt, Icefields, Maligne, Marmot, Miette Lake, Pyramid.

A complex persistent weak layer exists down 30-40cm. If you choose to brave the cold temperatures, pay attention to signs of instability such as cracking and whumpfing, and dig to assess this layer before committing to avalanche terrain.

Confidence

Moderate

Avalanche Summary

Field team in the Icefield area on Monday observed shooting cracks and whumpfing on surface hoar layer down 30 cm at tree line and below in sheltered east to northerly aspects. Nov 27th MIN report confirms the presence of the same layer of concern in the Maligne region. Marmot Ski Area reporting no recent results from explosive testing and control.

Snowpack Summary

30-40cm of snow overlies the November 16th Persistent Weak Layer, which is comprised of surface hoar and facets in sheltered locations tree line and below, and a crust on southerly aspects. The surface hoar/facet layer may extend into isolated alpine terrain. The strength of the lower snowpack is also deteriorating with recent cold temperatures. Height of snow ranges from 60 to 100cm.

Weather Summary

A ridge of high pressure with frigid temperatures will remain the dominant weather pattern over the area until Sunday.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.
Back off if you encounter whumpfing, hollow sounds, or shooting cracks.

Problems

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.

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.