Avalanche Forecast

Archived

Dec 24th, 2024–Dec 25th, 2024

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

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

Happy Holiday's everyone. Travel safe. Tangle weather station registered gusting 100km/hr winds and Maligne area is forecast to have steady high elevation 70 km/hr winds Tuesday to Thursday.

Confidence

Low

Avalanche Summary

No patrol occurred Monday or Tuesday and nothing new reported. Over the weekend the ski hill using explosives triggered two size 1.5 deep persistent avalanches and a small windslab. Lake Louise skihill to the South has been consistently explosive triggering windslabs size 1.5-2.

Snowpack Summary

Strong to extreme winds have redistributed surface snow and scoured windward aspects. Sheltered locations may still hold 15cm of soft snow if winds did not get to it. In protected areas, a weak layer of 7mm Surface Hoar may be 10-30cm down. The mid-lower snow pack has multiple layers of crusts and facets with one being near the ground.

Weather Summary

Icefield's area on Christmas day will be cloudy, flurries, -8 °C, SW winds 20 gusting to 60 km/h. Boxing day may bring similar weather with SW 15 gusting 40 km/h winds. Friday will be much the same as Thursday. Of note, Maligne could be blowing steady 40-70km/hr at upper elevations Wednesday to Thursday morning.

Terrain and Travel Advice

Be careful 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.