Avalanche Forecast

Archived

Apr 11th, 2026–Apr 12th, 2026

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

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

South Rockies, Bull, Crowsnest North, Crowsnest South, Elkford East, Elkford West.

Buried persistent layers bring uncertainty as warm temperatures continue.

Avoid exposure to large, overhanging cornices and steep, rocky start zones in the alpine.

Confidence

Moderate

We are uncertain about how persistent slabs will react to the forecast weather.
We are uncertain due to a limited number of field observations.

Avalanche Summary

No new avalanches were reported on Thursday or Friday.

On Wednesday, our field team reported a very large (size 2.5) persistent slab avalanche triggered by a cornice fall on Window Mountain, likely occurring on Tuesday, see photo below. Another large avalanche was observed on Saturday, most likely on the buried weak layer.

Observations from this region are currently limited. Please consider submitting a MIN to let us know what you're seeing out there.

Snowpack Summary

A lack of overnight refreeze will likely keep the snow surface moist/wet to mountain top.

A layer of weak facets above a crust is buried 50-70 cm deep. This remains a concern for triggering in the alpine by large loads such as a cornice fall or snowmobile in steep and rocky terrain.

Facets exist at the base of the snowpack in shallow areas. Snowpack depth tapers rapidly at lower elevations.

Weather Summary

Saturday Night
Mostly cloudy. 2 mm of rain. 30 km/h southwest ridgetop wind. Treeline temperature 2 °C. Freezing level 2500 m.

Sunday
Cloudy. 1 to 2 mm of precipitation as snow or rain at treeline. 20 km/h south ridgetop wind. Treeline temperature -1 °C. Freezing level 2000 m.

Monday
Mix of sun and clouds. 1 mm of precipitation as snow or rain at treeline. 10 km/h west ridgetop wind. Treeline temperature 0 °C. Freezing level 2100 m.

Tuesday
Mostly cloudy. 5 mm of precipitation as snow or rain at treeline. 50 km/h west ridgetop wind. Treeline temperature -1 °C. Freezing level 2100 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Cornice failures could trigger large and destructive avalanches.
In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and slopes above cliffs.

Problems

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.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.