Archived

Avalanche Forecast

Dec 5th, 2016–Dec 6th, 2016

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

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

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: Kootenay Boundary.

Wind slabs from the recent snowfall are expected to remain reactive to human-triggering. Field observations have been limited to date, so please share your observations on the Mountain Information Network (MIN) if you've been out in the mountains.

Confidence

Low - Due to the number of field observations

Weather Forecast

TUESDAY: Mix of sun and cloud, light north winds, alpine temperatures at -15.WEDNESDAY: Sunny, light winds, alpine temperatures at -16.THURSDAY: Isolated flurries, moderate southwest winds, alpine temperatures at -12.

Avalanche Summary

Although reports are limited, natural avalanche activity was reported in alpine terrain on Sunday and Monday, including loose dry avalanches and storm slabs up to size 2. Lingering wind slabs from the storm snow will likely remain reactive to human triggering at higher elevations in the upcoming days.

Snowpack Summary

25 cm of low density snow from the weekend is settling and will be thickest and most reactive on leeward features in wind exposed terrain. In some areas, the storm snow may sit above either a thin drizzle crust or small surface hoar layer, possibly making it more reactive. Surface hoar or surface facets will likely develop in the upcoming days, possibly creating a weak interface when the next storm arrives. A thick melt-freeze crust from mid-November is buried 40-80 cm deep. Facets have recently been reported above this crust, suggesting it may be possible to trigger this layer in shallow alpine start zones. The lower snowpack is generally strong and well-settled. Snowpack depths are 130-160 cm at treeline elevations.

Avalanche Problems

Wind Slabs

Lingering wind slabs from the weekend may still be reactive to human triggering in leeward features.

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

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 2