Avalanche Forecast
Issued: Mar 15th, 2018 4:52PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
cgarritty,
Avalanche Canada
Lingering wind slabs remain a concern on high elevation north aspects. Exercise increasing caution around solar aspects and lower elevations as loose wet avalanche conditions develop over the day.
Summary
Confidence
High -
Weather Forecast
Friday: Mainly sunny. Light variable winds. Freezing level to 1500 metres with alpine high temperatures of -3.Saturday: A mix of sun and cloud with increasing cloud and light flurries beginning in the afternoon. Light north winds. Freezing level to 1500 metres with alpine high temperatures of -3.Sunday: Cloudy with isolated flurries and a trace of new snow. Light northwest winds. Freezing level to 1400 metres with alpine high temperatures around -4.
Avalanche Summary
Reports from Monday included observations of three natural size 2.5 loose wet avalanches that released from steep, rocky, south-facing slopes in the afternoon in the Whistler area.On Sunday there was a report of a skier triggered size 2 storm slab avalanche on a west aspect at 2400m. On Saturday there were several size 2.5 natural persistent slab avalanches reported. These were suspected to have run in the previous 24hours and were observed on northwest to east aspects between 1900 and 2000m. Additionally there have been several observations of skier triggered storm and wind slab avalanche size 1-2 mostly on northerly aspects between 1800 and 2000m.
Snowpack Summary
About 10 cm of new snow accumulated over Tuesday night and Wednesday. In most areas the new snow buried a surface of variable crust and moist snow, the product of days of warm temperatures and sunshine. On high elevation north aspects, the new snow may overlie dry, wind redistributed snow from last week's storms. Last week's storms buried a weak layer composed of soft facets, surface hoar, and/or crust found roughly 50-100 cm below the surface. A week ago this layer was producing whumpfing, sudden results in snowpack tests, and even some remotely triggered avalanches. Much of this activity was attributed to buried surface hoar on north aspects at upper treeline elevations. This buried weak layer is a limited but lingering concern in a snowpack that is otherwise well settled and strong beneath this interface. Variable winds in the past month have built up cornices on many ridgelines. They will become touchier as daily temperatures rise and when they are subject to the strong late-winter sun on clear days.
Problems
Wind Slabs
Recent snowfalls formed wind slabs that still linger in north facing terrain. South aspects aren't exempt - they become an increasing concern over the day as sun and warming set up loose wet avalanche conditions.
Give cornices a wide berth while on or below ridges. Cornice falls may trigger large avalanches.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.Watch for wind-loaded pockets around ridgecrests and in the lee of exposed terrain features.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 16th, 2018 2:00PM
