Avalanche Forecast

Archived

Jan 31st, 2024–Feb 1st, 2024

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

Temperatures arn't quite dropping yet. Be patient while the avalanche hazard remains elevated this week from the ongoing heat.

Confidence

High

Avalanche Summary

Numerous natural avalanches at all elevations were observed over the past few days. Impressive avalanches up to size 3.5 out of alpine and tree line features, as well as loose wet and wet slabs up to size 2 below tree line were observed. Although natural avalanche activity is tapering slightly, the snowpack will remain unstable until the temperatures cool down.

Snowpack Summary

High freezing levels, rain, and solar radiation has formed breakable crusts up to 2500m. Below 2200m there is 5-10cm of moist snow on the surface until 1800m where the snowpack becomes saturated.

Previous Strong S and SW winds created wind slabs in alpine/treeline areas.

Persistent weak layers formed in early January are down 20-30cm in sheltered areas. Well developed facets and depth hoar make up the bottom of the snowpack.

Weather Summary

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

Thursday

Mainly cloudy. Alpine temperature High of 1 °C and freezing levels at 2400m. Mostly light ridge wind occasionally gusting to 35 km/h.

Friday

Mainly cloudy with scattered flurries (5cm). Alpine temperature: Low -3 °C, High 1 °C with freezing level at 2300m. Ridge wind light to 15 km/h.

Terrain and Travel Advice

Make conservative terrain choices and avoid overhead hazard.
Stick to non-avalanche terrain or small features with limited consequence.

Problems

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.

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 Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.