Avalanche Forecast

High -

Wednesday: A mix of sun and cloud with isolated flurries and a trace of new snow. Light southwest winds. Freezing level to 1800 metres with alpine high temperatures around -2.Thursday: Cloudy with wet flurries bringing 4-8 cm of new snow to high elevations with rain below about 1600 metres. Precipitation increasing and snow line falling overnight. Light southeast winds, becoming strong at higher elevations and increasing overnight. Freezing level to 2000 metres with alpine high temperatures around 0.Friday: Mainly cloudy with continuing isolated flurries and a trace to 5 cm of new snow. Moderate to strong southwest winds. Freezing level to 1200 metres with alpine high temperatures around -5.

Reports from Monday included observations of recent loose dry releases that reached size 2 as well as a recent natural size 2 storm slab release in the northern half of the region. The slab failed down 30 cm on a steeper east aspect in the alpine.On Saturday there were reports of small (size 1) skier and sled triggered slab avalanches (15 - 25 cm deep) on north and northeast aspects in the alpine. Explosive control work also produced several cornice failures up to size 2.5 that entrained loose snow on the slopes below but no deeper slab releases.Explosive control work last Friday produced size 1.5 slab avalanches averaging 20-60 cm deep on steep northerly features at treeline.

Recent light snowfalls (5-15 cm each) have been followed by warm daytime temperatures and glimpses of sun, setting up a couple of thin storm snow layers over temperature and sun crusts at lower elevations and on south aspects. On shaded aspects at higher elevations, Sunday's snowfall buried a layer of surface hoar now found 10-15 cm deep.New snow amounts taper with elevation and below 1700 m, only minimal accumulations have buried a supportive crust on all aspects. This crust will likely break down with daytime warming, becoming moist in the afternoon. Deeper persistent weak layers from mid-late February (down 40 -100 cm deep) as well as January and December layers are generally considered dormant, but could wake up with a surface avalanche stepping down, cornice fall, or a human trigger in a shallow or variable-depth snowpack area. These layers consist of sun crust, surface hoar and/or facets. Facets also linger at the base of the snowpack.