Avalanche Forecast

Moderate - Timing or intensity of solar radiation is uncertain on Sunday

We're looking at a series of weak weather systems for the next few days. Convective activity could result in locally higher accumulations, especially in the north. Temperatures are staying cool for this time of year. SUNDAY: A mix of sun and cloud with flurries (3-10cm, more possible in the north) / Light to moderate south west wind / Alpine temperature -7 / Freezing level decreasing to 1000m MONDAY: Mix of sun and cloud and occasional flurries / Light to moderate northwest wind / Alpine temperature -8 / Freezing level 1000m TUESDAY: Cloudy with isolated flurries / Light to moderate west wind / Alpine temperature -6 / Freezing level 1300m 

On Thursday, skiers triggered a size 2 wind slab that caught and carried a skier near Steep Creek in the Duffey zone. Slab thickness was 15-20cm. See this MIN post for more details. On Tuesday there was report of a skier triggered wind slab from the north of the region in the alpine near ridge top running on a layer of facets buried March 21. See this MIN post for more details. Reports on Monday from the north of the region show several skier triggered and natural storm slab avalanches size 1.5 to 2.5 running on either facets or surface hoar on north through east aspects in the alpine and tree line.

The past three days have seen only 3-9cm of new snow in most areas (with some higher amounts in isolated areas of the Coquihalla). Daytime warming created moist, heavy surface snow on sunny aspects, which refroze to form a crust overnight. Winds redistributed older snow to give a wide variety of surfaces: hard wind slabs, soft wind slabs on shady aspects, and the melt-freeze crusts on sunny aspects. Snow from a week ago sits on a deeper crust that is present at all elevations on sunny aspects as well as low elevation northerly aspects. On northerly and east aspects at treeline and alpine elevations the storm snow sits on a mix of large surface hoar and or facets.Deeper in the snowpack in the north of the region, north and east aspects are harboring cold snow and a surface hoar layer buried early March that is about 40-60 cm below the surface. This layer exists at alpine and treeline elevations, but it is not everywhere. This layer has produced large human triggered avalanches in the north of the region in the past week. In the south of the region, around the Coquihalla and in Manning Park, the last storm snow overlies a recent crust that caps a well settled snowpack.