Avalanche Forecast

Archived

Apr 2nd, 2023–Apr 3rd, 2023

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, St. Mary, Bull, Elkford East, Elkford West.

An unstable weather pattern will bring clouds, sun and flurries Monday. Sporadic flurries and wind will continue to promote wind slab formation at upper elevations.

Confidence

Moderate

Avalanche Summary

There have been no reports of recent avalanche activity in the region. That being said, a size 3 natural triggered deep persistent slab avalanche was reported March 28 in Highwood Pass in Kananaskis Country to the north. This was associated with warm temperatures and sun.

Snowpack Summary

New snow and wind are forming wind slabs at higher elevations.

The mid snowpack holds several persistent weak layers including layers of surface hoar in wind-sheltered terrain and sun crusts on south facing slopes. No recent activity has occurred on these layers.

The lower snowpack is made up of a widespread layer of large, weak basal facets and depth hoar in some areas. Neighboring Kananaskis Country reports continued avalanche activity on this layer. Avoid thin and rocky areas where this weak layer is more likely to trigger.

Weather Summary

Sunday Night

Mostly cloudy with scattered flurries, accumulation 1-3cm. Light southwest wind. Alpine high of -7 °C. Freezing level at valley bottom.

Monday

Mostly cloudy with sunny breaks and scattered flurries, accumulation 1-5cm. Light to moderate northeast wind. Alpine high of -4 °C. Freezing level 1400 m.

Tuesday

Mix of sun and cloud. Light east wind. Alpine high of -2 °C. Freezing level 1600 m.

Wednesday

Cloudy with sunny breaks. Light to moderate southwest wind. Alpine high of -3 °C. Freezing level 1500 m.

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.
Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

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.