Part of our region could see up to 45 cm of snow accumulate by noon on Monday.
Reactive storm slabs should be expected.
Significant snowfall, strong southwest winds, and warm temperatures hit our region Sunday night and will carry on into Monday. Use conservative decision-making as reactive storm slabs will be widespread.
Precipitation may arrive as rain at lower elevations. This may cause the upper snowpack to become saturated and cause wet loose avalanches in steep and rocky terrain.
A size 2.5 natural glide slab release was reported on Thursday. This avalanche occurred at treeline on a south aspect. No other significant avalanches were reported in the past few days.
Operators in the area reported natural wind slab activity Friday and Saturday. They were on the north and northeast and released at a depth of 10 to 40 cm.
Snow arriving Sunday night will sit on a variety of surfaces. On solar aspects, it may sit on a recently developed sun crust. In sheltered areas, the new snow will bury 10 cm of snow that fell earlier in the week. There are reports of a buried surface hoar layer underneath this layer of recent snow. Strong to moderate south to southwest winds may create new wind slabs at higher elevations. Cornices have also been created.
There are several crusts in the mid/lower snowpack. Their depth ranges from 150 to 250 cm.
A large trigger, such as a cornice fall or a smaller avalanche in motion, could trigger a very large avalanche on one of these deeply buried weak layers. A single rider is unlikely to trigger this layer unless they are in a steep, rocky, and shallow snowpack area.
Sunday Night
Cloudy, up to 30 cm accumulation mixed with rain, winds southwest 35 km/h gusting to 70, treeline temperatures -5 to 0 °C with freezing levels reaching 1500 m.
Monday
Cloudy, 10 to 15 cm accumulation, winds southwest 30 to 40 km/h gusting to 60, treeline temperatures -7 to -2 °C with freezing levels to 1100 m.
Tuesday
A mix of sun and cloud, trace accumulation, winds southwest 20 to 30 km/h, treeline temperatures around -5 °C with freezing levels going from 300 to 1400 m.
Wednesday
A mix of sun and cloud, trace accumulation, winds westerly 15 to 20 km/h, freezing levels getting up to 1600 m by the end of day.
More details can be found in the Mountain Weather Forecast.
