Avalanche Forecast
Regions: Sea To Sky.
Confidence
Fair
Weather Forecast
Synopsis: A weak weather system will bring more cloud and light precipitation to the South Coast for Tuesday and Wednesday. A ridge of high pressure should build in for Thursday and Friday bringing mainly sunny skies. Tuesday: Increasing cloud with light precipitation (2-4 cm). The freezing level will rise to around 1100 m during the day. Winds are light from the southeast. Wednesday: Cloudy with light precipitation (4-8 cm). The freezing level is around 1200 m and winds are light from the southeast. Thursday: A mix of sun and cloud. The freezing level is steady around 1200 m.
Avalanche Summary
A widespread natural avalanche cycle (with avalanches from size 2-4) occurred on Friday/Saturday in response to intense storm-loading. Numerous large, deep fracture lines can be seen from the Sea-to-Sky corridor. Many of these failed low in the start zone, leaving hangfire (unreleased areas of the slope). Natural avalanche activity slowed down on Sunday but explosive control continued to produce results up to size 3 and there were a couple reports of skier triggered avalanches up to size 2, primarily from north through east aspects in the alpine.
Snowpack Summary
Strong NW winds redistributed storm snow onto south and east aspects on Saturday. This reverse loading may have left wind slabs in unexpected locations.The recent storm delivered well over 100 mm of precipitation, which fell with warming temperatures, dropping rain below about 1500-1900 m, depending on location. Strong southerly winds during the storm created wind slabs on lee terrain. Numerous weaknesses developed within the storm snow. A weakness of surface hoar and/or a crust exists within the upper snowpack (now 1-2 m deep), which has been reactive over the last week, creating very large avalanches. Direct sunshine may trigger some further shedding of storm snow on Monday. The lower snowpack is well settled.
Avalanche Problems
Wind Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 4
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 6
Cornices
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 6