Register
Get forecast notifications
Create an account to receive email notifications when forecasts are published.
Login
Archived

Avalanche Forecast

Jan 18th, 2024–Jan 19th, 2024
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Recent persistent slab activity warrants conservative terrain selection.

New snow may form reactive storm slabs, in areas where a slab is not found dry loose avalanches are likely.

Confidence

Moderate

Avalanche Summary

On Wednesday, two persistent slab avalanches (size 1 and 2) were remotely triggered by skiers in the Northern Selkirks. These avalanches occurred on north aspects at treeline. Several natural and skier-triggered storm slabs were reported from alpine and treeline terrain up to size 2.

As snowfall continues on Friday, storm slab reactivity is expected to persist. Persistent slabs continue to be a concern and are best managed with conservative terrain choices.

Snowpack Summary

20 to 30 cm of low-density storm snow has buried a variety of snow surfaces. It sits above unconsolidated faceted snow, surface hoar and firm wind-pressed snow in open terrain at treeline and above.

Down 50 -70 cm, a crust, facet and or surface hoar layer exists. This may become a problem once the snow above starts to stiffen and form a slab.

130+ cm down another surface hoar layer exists that was buried in early December. This seems to be of most concern above 2000 m where a robust crust doesn't exist above it, or in shallow snowpack areas.

The depth of the snowpack varies greatly throughout the region and weak basal facets are present at the base of the snowpack.

Weather Summary

Thursday Night

Mainly clear, with cloud cover increasing in the early morning and no new snow. Alpine wind light from the southeast. Treeline temperature around -15 °C.

Friday

Cloudy with snowfall, up to 10 cm of accumulation. Alpine wind south 10 to 40 km/h. Treeline temperature rising to -10 °C.

Saturday

Cloudy with light snowfall, up to 5 cm of accumulation. Alpine wind south 10 to 30 km/h. Treeline temperature rising to -5 C.

Sunday

Cloudy with light snowfall, up to 5 cm of accumulation. Alpine wind south 10 to 30 km/h. Treeline temperature rising to -5 C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be aware of the potential for larger than expected storm slabs due to the presence of buried surface hoar.
  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
  • Be carefull with sluffing in steep terrain, especially above cliffs and terrain traps.

Avalanche Problems

Storm Slabs

Storm slabs may be touchier in wind affected terrain.

Dry loose power sluffing will likely exist in wind sheltered terrain, especially on steep slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 2

Persistent Slabs

Two weak layers of surface hoar exists deeper in the snowpack. They have recently been reactive and triggered by people. As the unconsolidated snow settles and forms a slab, a reactive upper snowpack may exist.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 3.5

Deep Persistent Slabs

Basal facets remain a concern in steep, rocky alpine features with thin-to-thick snowpack transitions.

Aspects: All aspects.

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3.5