Avalanche Forecast

Archived

Dec 26th, 2025–Dec 29th, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Kananaskis, Bow Valley, Highwood Pass, North 40, Spray - KLakes.

Cold temperatures are arriving for the weekend. Keep a keen eye out for windslabs as you move into more open treeline terrain and be prepared to adjust your route accordingly.

Confidence

Avalanche Summary

Numerous loose dry sluffs up to sz 1 were observed throughout the region in Alpine terrain. Forecasters were able to remotely trigger a sz 1.5 thin windslabs while travelling along a ridge at 2400m on Friday.

No new large slab avalanches were observed.

Snowpack Summary

15cm of snow fell overnight on the 25th with light to moderate SW winds.

Buried wind slabs and fresh windslabs from the snow over the past week are widespread in the alpine and on lee and cross-loaded features at treeline. Be sure to dig down an evaluate this potential and always be feeling with your pole and skis for that hollow feeling indicating you are on a supportive windslab. The November crust is now down 130-180cm, and is showing signs of faceting around this crust layer. Recent avalanches in the upper snowpack have stepped down to this interface producing large destructive avalanches.

Weather Summary

As the cooler temperatures push in overnight we can expect 5-8cm of snow to fall then...back into the -20s for a day or two! Winds will be light and it will be a mix of sun and cloud throughout the day.

https://hpfx.collab.science.gc.ca/~fsg006/productviewer/ab/table/AB_Rockies_Forecast.html

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Be mindful that deep instabilities are still present and have produced recent large 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.

Loose Dry

Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.