Archived

Avalanche Forecast

Feb 25th, 2014–Feb 26th, 2014

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

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

Regions: South Coast.

Forecast sun and high freezing levels may increase the danger from loose wet avalanches and avalanches stepping down to the deeply buried weak layer.

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Wednesday

Weather Forecast

Overnight and Wednesday: Clear overnight with freezing level down to valley bottom and light winds. Moderate Southwest winds and some cloud developing in the afternoon. Freezing level rising quickly to near 2500 metres.Thursday: Continued warm air in the alpine with moderate to strong Northerly winds developing during the day. Mix of sun and cloud during the day, clearing in the evening.Friday: Sunny and clear with strong Northwest winds and cooler temperatures.

Avalanche Summary

No new large avalanches reported. Some thin wind slab releases up to size 1.5 due to reverse loading were reported. Snow-balling and moist loose avalanches were reported from Southerly aspects. Extensive explosive control did not result in any releases on the deeply buried weak layer in the Coquihalla area on Tuesday.

Snowpack Summary

10-30 cm of cold low density new snow has fallen in the past couple days, accompanied by light to moderate W-NW winds. Older dense wind slabs may be lightly buried on a variety of aspects and in cross-loaded terrain features. In the southern portion of the region up to 200 cm of settled storm snow sits on a crust/facet combination buried in mid February. In northern sections this weakness includes surface hoar and is generally down 60-100 cm. Recent snowpack tests indicate that this weak layer may be gaining strength, but professionals remain suspect. The mid and lower snowpack are generally strong and well-settled. However, basal facets and depth hoar are likely to exist in the north of the region and still deserve respect on thin rocky alpine slopes.

Avalanche Problems

Persistent Slabs

The deeply buried weak layer continues to be sensitive to additional loads. Cornice falls or loose wet avalanches in motion may trigger the deep weak layer of facets and crusts.

Whumpfing, shooting cracks and recent avalanches are all strong indicators of unstable snowpack.>Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>Stick to simple terrain and be aware of what is above you at all times.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 2 - 6

Wind Slabs

Easterly outflow winds may have reverse loaded some slopes that had been previously stripped of storm snow. These new wind slabs may be easy to trigger.

Avoid freshly wind loaded features.>Be cautious as you transition into wind affected terrain.>

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 3

Loose Wet

Forecast solar radiation may release loose moist or wet snow avalanches. Avalanches in motion may step down to the deeply buried weak layer of facets and crusts.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>Minimize exposure to sun exposed slopes when the solar radiation is strong.>

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

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 3