Archived

Avalanche Forecast

Apr 8th, 2015–Apr 9th, 2015

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

Alpine

1: Low

The avalanche danger rating in the alpine will be low

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

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.

Stick to higher shady slopes for the best snow, but keep the persistent slab problem in mind when choosing your line.

Confidence

Good

Weather Forecast

Thursday: Mainly sunny. The freezing level climbs to around 2000-2200 m during the day and drops below 1500 m overnight. Winds are light and variable. Friday: Increasing cloud with snow possible late. The freezing level lowers to 1800 m and winds increase to moderate or strong from the S-SW. Saturday: Cloudy with periods of snow. The freezing level continues downward to around 1200-1400 m and winds are moderate from the SW.

Avalanche Summary

Moist loose avalanches have been reported on steep sun-exposed slopes, and one natural cornice fall (size 2) was reported on Monday. This cornice did not trigger a slab on the slope below.

Snowpack Summary

On shady slopes, 15-25 cm of cold low-density snow sits on a strong and supportive rain crust that was buried last Saturday and extends as high as 2100m. Expect an ongoing melt-freeze cycle on sun-exposed slopes. A facet/crust layer that was buried in mid-March is now approximately 50-100 cm down. Recently it was found down 55 cm near the Duffey Lake Road, and produced moderate sudden results. This remains a concern in the region because of it's potential for very large avalanches. Cornices are now large and mature and may collapse with daytime warming and intense sunshine.

Avalanche Problems

Persistent Slabs

A couple persistent weak layers are still present in the upper snowpack. These have not been reactive for a few days now, but intense spring sun or cornice falls could be enough to reawaken this problem.

Avoid convexities or areas with a thin or variable snowpack.>Be aware of thin areas that may propogate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 5

Loose Wet

Expect loose wet activity on steep sun-exposed slopes during the day.

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

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

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2

Cornices

Daytime warming and sunshine could weaken large overhanging cornices and cause them to fail. These are a hazard alone, but also a potential trigger for deeper weak layers.

Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 4