Avalanche Forecast

Archived

Feb 9th, 2025–Feb 10th, 2025

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

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

Assess whether there are slab properties in the surface snow as you travel through different terrain features.

Deep instabilities are still present at the base of the snowpack and are more likely to be triggered in shallow rocky areas.

Confidence

Moderate

Avalanche Summary

On February 5th, a size 2.5 Deep Persistent Slab avalanche was observed in the Churchill area along the 93N. It was triggered by cornice fall and stepped down to the Deep Persistent layer.

Snowpack Summary

The 10-25 cm from Feb 1st, mostly redistributed by wind, sits over top of a weak layer consisting of temperature crusts, winds slabs, or faceted snow. The midpack is weak and faceted. The early season crusts are faceting and breaking down but continue to persist along with large depth hoar at the base. The snowpack at tree line is 70-130 cm in the Icefields area and 50 cm in the Maligne area.

Weather Summary

Monday

Sunny with cloudy periods. Precipitation: Nil. Alpine temperature: High -17 °C. Ridge wind northwest: 10-25 km/h.

Tuesday

Cloudy with sunny periods and isolated flurries. Precipitation: Trace. Alpine temperature: Low -24 °C, High -18 °C. Mostly light ridge wind occasionally gusting to 35 km/h.

Wednesday

Sunny with cloudy periods. Precipitation: Nil. Alpine temperature: Low -24 °C, High -18 °C. Ridge wind west: 10 km/h.

Terrain and Travel Advice

If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

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.