Avalanche Forecast

Archived

Mar 14th, 2024–Mar 15th, 2024

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Regions

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

Afternoon Road Closures are anticipated on Maligne Lake Road and the Icefields Parkway (from Parkers Ridge to Saskatchewan Crossing)

Check AB511 for immediate updates

Confidence

High

Avalanche Summary

Numerous loose wet, snowballing, and pinwheels were observed on steep sunny aspects. Large slabs have been observed in alpine lee features near the Icefields.

Snowpack Summary

The forecasted warmup will be a dramatic change to the surface and mid-pack condition of the snowpack. This change will happen over an extremely reactive crust interface down 35-60cm. This persistent weak layer has been consistently producing large natural avalanches. The equally worrisome basal depth hoar makes up the bottom third of the snowpack. HS ranges from 80 to 130cm.

Weather Summary

Clearing overnight Thursday

Parker Ridge - Friday

Sunny with cloudy periods on Friday. No new precip.

Alpine temperatures: High 3 °C.

Mostly Light SW winds.

Freezing level: 2600 m

Saturday

Sunny. Low -1 °C, High 6 °C.

Freezing level: 3200 m

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

Terrain and Travel Advice

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Problems

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.

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.

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.