Avalanche Forecast

Archived

Feb 21st, 2025–Feb 22nd, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

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.

Regions

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

The Icefields Parkway will be closed for avalanche control from Athabasca Falls to Saskatchewan Crossing starting Saturday at 4 PM. Check for updates on https://511.alberta.ca/.It is time to reel back from avalanche terrain while the snowpack is going through significant changes over the weekend.

Confidence

Low

Avalanche Summary

A few small loose point release avalanches observed on a field day around Parker Ridge on Thursday.

Snowpack Summary

Warm temperatures are making the surface snow moist below 2000m and on south facing terrain. The Icefields is wind affected even into treeline. In sheltered areas there is roughly 15cm of snow overlying the January 30th layer which is a temperature crust or wind slab depending on the area. The midpack is weak and faceted. The bottom of the snowpack is comprised of large depth hoar.

Weather Summary

Weather models are not in agreement on the forecast for precipitation, freezing levels, or wind speed. The snow accumulation for the weekend ranges from 15 to 60 mm, with the majority of precipitation expected to arrive Saturday night. Freezing levels may rise to 2000 m, with strong to extreme southwesterly winds. Be sure to check local telemetry stations before heading out to verify the forecast on the ground.

Terrain and Travel Advice

Be careful as you transition into wind-affected terrain.
If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Avoid areas with overhead hazard.

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.