Summary
Confidence
Fair - Freezing levels are uncertain for the entire period
Weather Forecast
Saturday: A mix of sun and cloud. Freezing level around 1700 m. Minimal wind.Sunday: Warm and dry, with increasing cloud and winds increasing from the SW in the afternoon. Freezing level around 1600 m. Monday: Light to moderate precipitation, mostly falling in the early morning. Moderate SW winds. Freezing level around 1600 m.
Avalanche Summary
Recent reports include cornice fall and loose wet avalanches. Full-depth size 2-3 glide avalanches have been releasing on rock slabs.
Snowpack Summary
Rain fell to 2000 m on Wednesday. Ongoing warm temperatures and the rain have caused the surface snowpack layers to become isothermal (at 0 °C), even on north aspects, to about 2100 m. This is expected to have formed a crust in most areas, now covered by a small amount of new snow. Very large cornices are looming. 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. A buried crust/surface hoar layer from late March, within the upper 1.5 m of the snowpack, is reported to have gained strength in the Duffey Lake area, but remains a lingering concern.
Problems
Cornices
Mammoth cornices are looming. A cornice fall can act as a heavy trigger for avalanches on the slope below.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Wet Slabs
Wet loose or slab avalanches are most likely on steep slopes when temperatures are warm, especially at low elevations. Avoid exposure to slopes which are sporting glide cracks.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 14th, 2012 9:00AM
