Avalanche Forecast

Issued: Apr 19th, 2013 10:30AM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs, Loose Wet and Cornices.

jlammers, Avalanche Canada

Sea To Sky.

Summary

Confidence

Good

Weather Forecast

Light snowfall is forecast for Saturday. Moderate west winds are expected with freezing levels at about 1800m. On Sunday and Monday the region should see generally clear skies, light north winds and freezing levels at about 1500m.

Avalanche Summary

No new avalanches have been reported from the region.

Snowpack Summary

Variable amounts of snow fell throughout Thursday night and Friday with the greatest accumulations falling in the south of the region. More recent rain and warm temperatures have left snow surfaces moist to about 1950m. Cohesive new wind slabs are likely to exist at higher elevations.In the upper snowpack (down 50-70cm) a significant melt-freeze crust lingers. Some facetting has been observed above and below this crust. At the same interface spotty surface hoar may linger on high, sheltered north facing terrain. My best guess is that this interface has gained significant strength, although I would make further observations before committing to any steep, unsupported features in the alpine.Cornices are huge and will continue to grow with the forecasted precipitation.

Problems

Wind Slabs

New softslabs exist in lee terrain at higher elevations, particularly in the south of the region where recent accumulations have been highest.

Stay off recent wind loaded areas until the slope has had a chance to stabilize.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Loose Wet

Watch for loose wet avalanche activity in steep terrain, especially if the sun comes out on Saturday.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Cornices

Cornices are gigantic and may become weaker with additional wind and snow.

Pay attention to overhead hazards like cornices.>Cornices become weaker with daytime heating.>

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 6

Valid until: Apr 20th, 2013 2:00PM