Small but reactive wind slabs may form as storm snow accumulates on eastern slopes.
Continue to avoid large and consequential terrain while the snowpack cools and strengthens.
Watch for reactivity in wind-affected features where fresh snow has fallen. Although storm totals are small, slabs may slide easily on the crust below.
Multiple weak layers in the top meter of the snowpack remain a concern.
If triggered, this problem will likely be the full depth of the snowpack and could run below treeline. Avoid shallow, rocky start zones.
We expect wind slab avalanche activity to increase on Sunday with cooler temperatures and fresh snowfall.
By Sunday afternoon storm totals are expected to reach 10 in most areas, with hotspots of up to 20 cm possible on the eastern slopes of the Purcells. This snow accumulates over a crust that varies in thickness and elevation throughout this forecast area. In the Dogtooth Range, this crust thins into the alpine and becomes breakable.
The top 50 cm of snow at treeline is moist with several layers of crusts and facets below. At the base of the snowpack, weak faceted grains and depth hoar is present. While cooler temperatures are expected to help these layers to strengthen we continue to monitor them for signs of reactivity.
Saturday Night
Cloudy with up to 15 cm of new snow expected, favoring the eastern slopes of the Purcells. Northeast winds 10-30 km/h. Freezing levels around 1500 m, treeline temperatures near -4 °C.
Sunday
Mostly cloudy with up to 5 cm of new snow expected. Freezing levels around 1000 m, treeline temperatures around -8 °C. Easterly winds ease, 10-20 km/h.
Monday
Mostly cloudy with possible flurries. Freezing levels reach 1000 m, treeline temperatures around -8 °C. Southerly winds 10-20 km/h.
Tuesday
Mostly cloudy with possible flurries. Freezing levels reach 1300 m, treeline temperatures around -6 °C Southerly winds 10-20 km/h.
More details can be found in the Mountain Weather Forecast.
