Avalanche Forecast

Archived

Dec 12th, 2023–Dec 13th, 2023

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

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

Natural avalanches possible, human triggered probable.

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.

Human triggered avalanches remain possible. It is prudent to remain vigilant, evaluate snow and terrain carefully, and ski lightly as a myriad of early season hazards lurk just below the surface.

Confidence

Moderate

Avalanche Summary

Tuesday's Patrol had excellent visibility and nothing new was observed.

Snowpack Summary

The snowpack is 40-60cm deep and is weak and facetted. A surface hoar layer down 15-20cm. A rain crust exists below 1800m. Previous strong wind has stripped exposed alpine.

Weather Summary

The Mountain Weather Forecast is available at Avalanche Canada https://avalanche.ca/weather/forecast

Wednesday will be a mix of sun, clouds, flurries, High -7 °C, and light SW winds. Expect a temperature inversion and possibly gusting 70km/hr winds Wednesday. Thursday could bring 9cm of snow, -4 °C, light winds, and 1600 metre freezing level. Friday-Saturday will return to clouds, sun, and -11 to -7 °C.

Terrain and Travel Advice

Avoid areas where the snow feels stiff and/or slabby.
Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.

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.