Archived

Avalanche Forecast

Apr 3rd, 2017–Apr 4th, 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

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

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

3: Considerable

The avalanche danger rating below treeline will be considerable

Regions: Jasper.

Daytime and solar heating will weaken cornices, avoid traveling in avalanche terrain during periods of intense solar input.

Weather Forecast

Clear skies with no forecasted snow as a shallow ridge of high pressure moves into our area on Tuesday. Winds will be light from the West with an alpine high of -6 with freezing levels rising to 1500m. Light flurries on Wednesday into Thursday with freezing levels to 2000m.

Snowpack Summary

10cm of new snow in past 2 days has formed windslab along lee ridge-lines and cross-loaded gully features from SW winds. Mid-pack bridging basal weakness. Entire lower snowpack is weak with a combination of facets, Nov rain crust and depth hoar. Below tree line a 5-10cm melt freeze crust sits above a moist facet layer to ground.

Avalanche Summary

No new avalanche observations on Monday, but previous cornice and windslab failures have triggered the deep persistent slab resulting large full path avalanches. Loose wet avalanches have previously occurred on steep south and west aspect below tree-line.

Confidence

Timing or intensity of solar radiation is uncertain on Tuesday

Avalanche Problems

Loose Wet

Prolonged solar radiation and rising freezing levels with weaken the snowpack on South and West aspects, especially around steep and rocky areas.

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

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 2

Cornices

Cornice failure is hard to predict but is more likely with inputs like solar radiation and wind-loading.

Give cornices a wide berth when travelling on or below ridges.Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 2 - 3

Deep Persistent Slabs

This problem is unlikely to disappear. It can be triggered by large loads like cornice fall or windslab failure. Human triggering is most likely from shallow spots or on steep unsupported slopes.

Be cautious in shallow snowpack areas where triggering is more likely.Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 4