Avalanche Forecast

Archived

Jan 8th, 2024–Jan 9th, 2024

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

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.

Regions

Banff Yoho Kootenay, Little Yoho, Banff, East Side 93N, Kootenay, Lake Louise, LLSA, Sunshine, West Side 93N, Field.

Strong winds forecasted on Monday night/Tuesday morning will increase the likelihood of windslab development in the alpine and exposed treeline terrain. Pay attention for this change as you transition through the treeline.

Confidence

Moderate

Avalanche Summary

Several loose dry avalanches were observed out of steep alpine terrain on Monday. Sunshine Ski Resort reported ski cutting small windslabs from steeper terrain.

There was a skier accidental avalanche size 1.5 near the Lake Louise ski area on Saturday.

Snowpack Summary

10-25cm of recent storm snow sits over a variety of surfaces (sun crusts, surface hoar, old wind slab) at treeline and above. Some sluffing and windslab development can be found in steep exposed terrain.

The mid pack is settled and mostly supportive. It contains several melt-freeze crusts which can be found as high as 2300m in southern areas. The base of the snowpack consists of a mix of weak facets and depth hoar.

Treeline snow depths range from 65-110 cm.

Weather Summary

Flurries are forecasted through Wednesday with total accumulations in the 10-15 cm range.Winds will start out strong (SW) on Tuesday and decrease in afternoon, becoming light-mod by Wednesday.Daytime highs on Tuesday will be around -10, but will start falling on Wednesday becoming very cold (-25-30) by Thursday.

For more information, click Mountain Weather Forecast.

Terrain and Travel Advice

Be carefull around freshly wind loaded features.
Avalanche hazard may have improved, but be mindful that deep instabilities are still present.

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.

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.

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.