Avalanche Forecast

Archived

Jan 15th, 2025–Jan 16th, 2025

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.

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.

Snow and weather conditions are expected to continue changing throughout the day and into tomorrow.

Incoming snow and wind will create new windslabs, avoid open slopes that may have the potential for wide propagation.

Confidence

Moderate

Avalanche Summary

Tuesday road patrol observed few small wind slab avalanches initiating at ridge tops and running as loose dry for short distance. Marmot Basin reported a small natural avalanche scrubbing to ground in the alpine on north aspect, suspected to be triggered out of steep rocky terrain

Snowpack Summary

The snowpack is 60-120cm in depth at tree line. Yesterday's moist surface snow to 2300m has refrozen. A weakening melt freeze crust and surface hoar layer from early December remains down 10-30cm. The middle of the snowpack is facetted and there is a deep persistent layer at the base of the snowpack consisting of a decomposing melt freeze crust and depth hoar.

Weather Summary

Thursday

Snow accumulation: 6 cm. Alpine temperature: High -6 °C. Ridge wind west: 30 km/h gusting to 80 km/h. Freezing level at valley bottom.

Friday

Thursday

Mainly cloudy with scattered flurries. Accumulation: 5 cm. Alpine temperature: High -4 °C. Mostly light ridge wind occasionally gusting to 45 km/h. Freezing level at valley bottom.

Saturday

Sunny with cloudy periods. Precipitation: Nil. Alpine temperature: Low -21 °C, High -17 °C. Ridge wind light to 20 km/h.

Terrain and Travel Advice

Approach lee and cross-loaded slopes with caution.
Be careful with wind-loaded pockets, especially near ridge crests and rollovers.

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.