Avalanche Forecast

Fair - Timing, track, or intensity of incoming weather is uncertain for the entire period

The timing and intensity of a series of fronts affecting the area is uncertain. The general picture is for the rest of the week to be stormy.Wednesday: Cloudy, with snow developing in the morning and continuing overnight. Freezing level around 1000m. Moderate to strong south-westerly winds. Thursday: Moderate to heavy snow. Moderate to strong south-easterly winds. Freezing level around 1500m.Friday: Moderate snow. Freezing level falling to around 1000m.

On Monday, natural avalanches to size 2.5 were reported, some possibly triggered by cornice fall. Last week, warming prompted a widespread natural cycle in the Coquihalla and skiers triggered very touchy persistent slabs at low elevations. An unnervingly large natural avalanche cycle occurred at the start of this month, with slabs up to size 4.5 propagating 2-3km along ridgelines and stepping down to the mid-February layer. Similar avalanches remain possible as storm loading continues this week.

Strong winds and snow have created wind slabs and storm slabs which are likely to fail in steep terrain, and could overload persistent weak layers. Persistent weak layers are variable in distribution across the region. A hollow series of poorly-bonded crusts was reported on southerly aspects in the Duffey Lake and Chilcotin regions last week, which may have healed somewhat with dramatic warming at the end of last week. A lower weakness comprising surface hoar, facets and a crust, has produced whumpfs and sudden planar ("pops") results in snowpack tests. It is still is a key concern for step-down avalanches in many parts of the region. It is especially prevalent on south-facing slopes above treeline, and all slopes below treeline.