Archived

Avalanche Forecast

Dec 30th, 2018–Dec 31st, 2018

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

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

2: Moderate

The avalanche danger rating below treeline will be moderate

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

Regions: Kootenay Boundary.

The forecast calls for a stable weather pattern in the next few days.

Confidence

Moderate -

Weather Forecast

MONDAY: Mix of sun and cloud / Light north wind / Alpine temperature -10 CTUESDAY: Mix of sun and cloud / Light northwest wind / Alpine temperature -4 C with a possible temperature inversionWEDNESDAY: Flurries / Moderate southwest wind / Alpine temperature -4 C / Freezing level 600 m

Avalanche Summary

Recent reports from Saturday indicate widespread thin storm slab avalanche activity size 1-1.5 that were 15cm deep with a some avalanches running to size 2 where thicker wind deposits existed (up to 40 cm). These were reported as explosives triggered, naturally triggered and some skier controlled.

Snowpack Summary

20-40 cm of snow sits on a thin sun crust on southerly aspects and small feathery surface hoar in sheltered areas.Beneath this, around 50 to 100 cm of snow sits on a rain crust and a weak layer of feathery surface hoar and sugary facets. Although there has not been a reported avalanche on this layer in over a week, snowpack test results tell us that it is still possible to trigger. The lower snowpack is well-settled.

Avalanche Problems

Wind Slabs

15-30cm of new snow combined with southwest winds have created deeper deposits in lee terrain in the alpine and tree line.

Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.

Aspects: North, North East, East, North West.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Persistent Slabs

A weak layer buried around 50 to 100 cm is still the main concern. Although avalanche activity has been quiet for the past week, the widespread nature of the layer and snowpack test results suggest that it is still a layer to be concerned about.

Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.Choose low-angle terrain without overhead exposure and watch for clues of instability.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3