Avalanche Forecast
Issued: Feb 10th, 2017 3:52PM
The alpine rating is Storm Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Moderate - Forecast snowfall amounts are uncertain on Saturday
Weather Forecast
Friday night: Cloudy with scattered flurries and about 5 cm of new snow. Winds strong to extreme from the southwest.Saturday: Periods of snow delivering 15-25 cm of new snow. Winds extreme from the southwest. Freezing level rising to 700 metres with alpine temperatures around -5.Sunday: Continuing snowfall with 15-25 cm of new snow accumulating. Winds extreme from the southwest. Freezing level to 1100 metres with alpine temperatures around -1Monday: Cloudy with scattered flurries and 5-15 cm of new snow. Winds strong to extreme from the south. Freezing level to 1300 metres with alpine temperatures possibly exceeding 0.
Avalanche Summary
No new avalanches were reported in the past few days. On Saturday, expect a transition from our previous wind slab problem to a more generalized and increasing storm slab problem as new snow accumulates and extreme winds promote rapid slab formation. Keep in mind that a basal weakness continues to drive a low probability/high consequence problem for shallow snowpack areas, especially in the north of the region.
Snowpack Summary
New snow over Friday night will begin to cover the widespread wind affected surfaces that have recently been reported in exposed terrain, including scoured surfaces, sastrugi, and hard wind slabs. In areas sheltered from the wind, the surface snow now being buried was recently reported faceting with surface hoar developing in open areas. Below around 1100 m elevation, a rain crust can be found near the surface of the snowpack. Deeper in the snowpack, the mid-January surface hoar/facet layer is now typically down 70-100 cm. Recent observations suggest the layer has generally stabilized but isolated weaknesses may still exist, especially where buried surface hoar is still intact. Below this layer, the snowpack is generally strong and well settled. The exceptions are areas around Bear Pass and Ningunsaw where basal facets remain an ongoing concern, especially in shallow snowpack areas.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 11th, 2017 2:00PM