Summary
Confidence
Poor - Freezing levels are uncertain
Weather Forecast
Friday: Clouds and a few cm of snow, falling as rain below treeline. Freezing level around 1200 m. Light northerly winds.Saturday: Mainly cloudy, with sunny breaks. Some lingering light precipitation is possible in the morning, becoming dry by afternoon . Light, variable winds. Freezing level around 1200 m.Sunday: Mainly cloudy. Freezing level near 1500 m. Light winds, increasing from the SW by evening as a low pressure system approaches.
Avalanche Summary
Several natural glide avalanches were reported this week on E to SW aspects below treeline, in the size 2-3.5 range. Wet loose avalanches up to size 2.5 were also observed in response to warming and sunshine. Last week, a large icefall triggered a slab in the Bear Pass area, creating a size 4 avalanche.
Snowpack Summary
Glide cracks have opened up and pose the threat of large, full-depth releases, especially on steep rocky terrain features at low elevations. Otherwise, a relatively strong and deep spring snowpack exists, which becomes weak during periods of warm weather or rainfall. Recently, a lack of overnight freezing below about 1500m has left the snowpack weak. Large cornices and ice cliffs pose a threat from above. Pockets of dry snow and surface hoar may still be found on high north aspects. Areas of wind slab may exist near ridge crests.
Problems
Wet Slabs
Warm temperatures or rain may continue to weaken surface snow, especially below treeline. Wet slides can push you around, entrain mass and become surprisingly large. Avoid traveling on or underneath any slopes which sport glide cracks.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Overhead hazards including cornices and ice cliffs can act as a heavy trigger for very large avalanches on the slope below.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 13th, 2012 9:00AM
