Avalanche Forecast
Issued: Feb 19th, 2016 8:25AM
The alpine rating is Storm Slabs and Cornices.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Moderate - Track of incoming weather systems is uncertain on Sunday
Weather Forecast
The last in the series of storms fizzles out Saturday morning. Unsettled conditions will continue through Saturday bringing mostly cloudy skies with some clearing later in the day. Alpine temperatures near -6 with freezing levels falling to 1000m. Ridgetop winds will blow light from the southwest. Sunday morning could see strong outflow winds along coastal inlets with the next Pacific frontal system rolling in by the evening. This could bring anywhere from 5-15 cm, accompanied by strong southerly winds and freezing levels near 1100m. Monday will remain unsettled with cloudy skies and flurries.
Avalanche Summary
On Thursday, a skier remotely triggered a size 1.5 wind slab from a gully feature on an easterly aspect at 2300m. Explosives control showed numerous size 2 storm slab releases from 1900-2300m. Storm slab avalanches are expected to be remain reactive to human-triggering with ongoing snowfall and wind, especially if the sun pokes out on Saturday. Cornices are reported to large and fragile, and may fail under the weight of a person.
Snowpack Summary
Recent storm accumulations are 50-80cm over the past week. This snow overlies a thick rain crust which extends into the alpine. The snow is reported to be bonding well to the crust and all the recent avalanches have been failing within the recent storm snow, not on the crust interface. At treeline and below, other crusts may exist in the upper snowpack due to the recently fluctuating freezing levels. As the freezing level continues to drop, a crust is expected to form at lower elevations. Ongoing southeast through southwest winds have been loading leeward features in the alpine and large cornice development has been reported over the last few days. The weak surface hoar layer from early January can be found down over a meter and is still reactive in isolated snowpack tests but triggering an avalanche on this layer has become unlikely.Â
Problems
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Feb 20th, 2016 2:00PM