Avalanche Forecast

Issued: Apr 9th, 2012 4:00PM

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

pgoddard, Avalanche Canada

Sea To Sky.

Summary

Confidence

Fair - Freezing levels are uncertain

Weather Forecast

Tuesday: Scattered light precipitation. Freezing level around 2000 m. Light southerly winds.Wednesday/Thursday: Light precipitation. Freezing level around 1900 m on Wednesday and 1500 m on Thursday. Light southerly winds.

Avalanche Summary

Recent observations include several loose-wet avalanches up to size 2 from steep solar aspects and wet slabs triggered by skiers below 1400 m. There has been some cornice fall and ice fall. On Sunday, a few small wind slabs were observed at ridge top. Last week, large slabs were suspected to have failed on the late-March interface.

Snowpack Summary

A melt-freeze crust exists on solar aspects and at low elevations. In some areas, limited overnight cooling has kept surface snow from re-freezing, leaving it loose and cohesionless. Surface hoar exists on shady slopes up into the alpine. Pockets of wind slab formed with recent southerly or easterly winds. Dry settling or faceting snow can be found on high north aspects. A predominately crusty weak interface from late March, now down 50-150cm, has become less likely to trigger, but remains a potential failure layer for large slab avalanches.

Problems

Wet Slabs

Warm temperatures may continue to weaken surface snow. Wet slabs and loose wet avalanches can push you around, entrain mass and become surprisingly large. Also, avoid traveling on or underneath any slopes which have glide cracks.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 4

Wind Slabs

Touchy wind slabs exist below ridges in some areas. These can be triggered by the weight of a person.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

Persistent slab avalanches have become less likely, but large avalanches remain possible, especially with a large trigger like cornice fall.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 7

Valid until: Apr 10th, 2012 9:00AM