Archived

Avalanche Forecast

Feb 5th, 2012–Feb 6th, 2012

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: Northwest Coastal.

Avalanche danger will peak during the heat of the day.

Confidence

Good - -1

Weather Forecast

Monday-Wednesday: Dry weather. Freezing level dropping to valley floor at nights and rising to around 1000m during the day. An above freezing layer is forecast for Tuesday between 1500m and 2500m. This means alpine temperatures could be above 0C. Light winds.

Avalanche Summary

Numerous solar-triggered avalanches to size 2.5 were observed on Saturday on slopes facing the sun. A few isolated slabs to size 2 were also reported from steep wind-loaded features near ridge top.

Snowpack Summary

Temperatures have been unseasonably warm, leading to moist or wet weak surface snow conditions. Where a re-freeze has occurred, a breakable crust now exists. Recent storm snow appears to be gaining strength. A facet layer buried on Jan 20th still exhibits hard, sudden planar results in isolated snowpack tests. It's about 120-150cm deep in the snowpack. At high elevations, large cornices and some wind slabs are causing concern. Cornices will be weakest during the heat of the day and have the potential to act as a trigger for deep avalanches on the slope below.

Avalanche Problems

Loose Wet

Warm temperatures and direct sun can trigger loose wet avalanches, particularly in steep south-facing terrain. This problem will spike during the heat of the day, so manage the timing of your exposure to sunny slopes.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 5

Wind Slabs

Hard wind slabs exist behind ridges and terrain breaks in some areas. Large cornices also exist, which could trigger an avalanche on the slope below if they fall.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 2 - 6

Persistent Slabs

A weak layer of buried facets has produced a few avalanches this week. Chances of triggering an avalanche on this layer have gone down, but could still occur with a large trigger like a cornice fall or airborne sled.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 3 - 8