Avalanche Forecast

Archived

Mar 5th, 2024–Mar 6th, 2024

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 possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

East Kakwa, Kakwa, Pine Pass, Tumbler.

Continue to choose conservative, low consequence terrain

The Likelihood of triggering a persistent slab is uncertain

Confidence

Moderate

Avalanche Summary

Only a few natural size 1.5 wind slab avalanches have been reported over the past few days.

Over the past week in the neighbouring region, many natural and skier triggered persistent slab avalanches occurred on the facets above the early-February melt-freeze crust described in the Snowpack Summary.

Snowpack Summary

Winds have come from a variety of directions over the past couple days. Wind effect could be found on all aspects.

30 to 50 cm overlies a layer of surface hoar in wind-sheltered terrain, weak facets, or a hard melt-freeze crust on south and west-facing slopes.

A thick and hard widespread crust that formed in early February is buried about 60 to 80 cm deep. This crust may have a layer of facets above it.

The eastern portion of this region is much shallower with a highly variable and wind effected snowpack.

Weather Summary

Tuesday Night

Clear skies. 10 to 20 km/h southwest alpine wind. Treeline temperature -21°C.

Wednesday

Sunny in the morning, increasing cloud in the afternoon. 15 to 35 km/h southwest alpine wind. Treeline temperature -14°C.

Thursday

Mostly cloudy with up to 5 cm of new snow. 25 to 40 km/h southwest alpine wind. Treeline temperature -6°C.

Friday

Cloudy with up to 20 cm of new snow expected. 30 to 50 km/h south alpine wind. Treeline temperature -1°C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Conservative terrain selection is critical, choose only well supported, low consequence lines.
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.
Remote triggering is a concern, watch out for adjacent and overhead slopes.

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.

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.