New snow, strong winds, and warm temperatures are creating conditions for a natural avalanche cycle.
Mt. Bourgeau and Eagle Mountain avalanche closure zone is CLOSED on Tuesday, January 13. For more information, follow the link above.
Surface hoar buried January 3 sits 30–60 cm deep. Warming may help stiffen the overlying slab and increase reactivity where this layer exists. While not widespread, recent reports include small avalanches failing on this layer. Dig down and test for reactivity.
Warm temperatures, new snowfall, and strong winds will continue to build surface slabs.
Basal facets remain near the ground. Red flags are fewer where the snowpack is deep, but on the eastern side of the forecast area, particularly in thin to thick snowpack transitions, the potential for deep slab avalanches remain.
Storm cycle in effect. The combination of new snow, strong winds, and warm temperatures is promoting a natural avalanche cycle. Local ski hills reported continued loading on exposed terrain at alpine and treeline elevations throughout Monday. We expect natural avalanche activity to peak on Tuesday.
30-60 cm of recent storm snow with W-SW wind has formed windslabs. In sheltered areas below treeline, this new snow sits on a layer of surface hoar buried on Jan 3, but this layer is not widespread and more prominent on Hwy93S and in Yoho.
There is 50-90 cm over the Dec 15 melt-freeze crust, present to 1800-2000 m, and 100-200 cm over the November facet/crust interfaces. In thinner snowpack areas, facets are present at the base
A westerly flow will bring more precipitation with accumulation values between 15 to 50 cm, and rain at lower elevations. Precipitation to taper on Tuesday, with a clearing trend developing in the afternoon. Temperatures will continue to rise through Wednesday, with freezing levels reaching 2000 to 2500 m at the peak of the warmth. Winds will remain strong over the next few days and begin to taper on Thursday.
