Archived

Avalanche Forecast

Dec 1st, 2017–Dec 2nd, 2017

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

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

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: South Coast.

Heavy snowfall in the North Shore mountains (>40cm storm snow into Friday) will take time to settle and bond to a crust. Dial back your terrain selection until conditions stabilize.

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

Precipitation will taper on Saturday, giving way to a clearing trend on Sunday and fine (warm) weather early next week.Saturday: Scattered flurries with up to 10 cm new snow. Freezing levels around 900 m. Moderate southerly winds.Sunday: Dry with some sunny breaks. Light northwesterly winds. Freezing levels 800m.Monday: Sunny with cloudy periods. Freezing levels around 700 m. Light northwesterly winds.

Avalanche Summary

Storm slabs were easily triggered by ski cutting on Thursday into Friday. See here for a good video of how easily the snow was moving on Thursday. We also had a fine MIN post describing storm slab activity on Mt SeymourExpect human triggered and natural avalanches to occur in steep, wind-affected terrain at higher elevations.

Snowpack Summary

50-70 cm of new snow overlies a crust at treeline elevations. Winds were moderate from the south east, resulting in reactive slabs, especially on lee features. Travel in many places is rugged below treeline, with many open creeks, alder and other early season hazards, although things should be improving with recent new snow. Expect snow depths of around 20 cm at 800 m and around 160 cm at 1200 m.

Avalanche Problems

Storm Slabs

Recent snow and wind will likely promote slab avalanche conditions in steep and/or exposed terrain.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.Avoid steep convex slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely - Very Likely

Expected Size: 1 - 3