Avalanche Forecast
Regions: Purcells.
Confidence
Good - -1
Weather Forecast
Temperatures should drop down to about -12.0 in the alpine by Wednesday morning. The ridge of high pressure is expected to continue to bring clear skies and light winds during the day Wednesday. Alpine temperatures may rise above freezing on solar aspects, but should remain slightly below freezing on shaded aspects. Cloud should move into the region overnight and precipitation is expected to begin by about noon on Thursday. Western parts of the region may get 5 cm combined with moderate southerly winds. The freezing level should rise to 900 metres during the day and drop back to near valley bottom overnight. Another ridge is forecast for Friday that should bring mostly clear skies and light winds during the day.
Avalanche Summary
One size 2.0 explosive controlled release did release a piece of cornice that triggered the slope below down to the ground. One operator reported that a large natural ice fall released and did not trigger the slope below.
Snowpack Summary
Widespread surface hoar has been buried by a couple of cm of new snow in most of the region. A melt-freeze crust has developed on southerly aspects at all elevations. North and east aspects continue to have dry snow and some surface hoar sloughing in steep terrain. The January 13th surface hoar layer is buried about 40 cm below the surface, and may still be reactive in thinner snowpack areas. Basal facets have not been reactive, but operators continue to monitor this layer in tests. Triggering this deep persistent weak layer is unlikely, but shallow snowpack areas or shallow weak areas adjacent to deeper wind loaded slopes are suspect locations.
Avalanche Problems
Cornices
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 5
Deep Persistent Slabs
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Unlikely
Expected Size: 3 - 7