Avalanche Forecast

Moderate - Recent weather patterns have resulted in a high degree of snowpack variability within the region.

SUNDAY NIGHT: Partially cloudy. Moderate westerly winds. Freezing level valley bottom. 

MONDAY: Partly cloudy with isolated flurries. Strong westerly winds. Alpine high temperature -12 C. Freezing level valley bottom. 

TUESDAY: Increasing cloud. Moderate to strong southwest winds. Alpine high temperature -12 C. Freezing level valley bottom.

WEDNESDAY: Cloudy with strong westerly winds and light snow. Freezing level below 1000m. 

The Purcells currently has a complex snowpack - with several reactive persistent weak layers in the mid and lower snowpack.

Two Mountain Information Network (MIN) reports (MIN 1 and MIN 2) on Friday, Dec 3 from Quartz Creek report deep persistent avalanches failing at the base of the snowpack. While its unknown if the images MIN 2 cover the same rider-triggered avalanche avalanche reported in MIN 1, they certainly highlight weak and reactive snow at the base of the snowpack.

A MIN report submitted yesterday from the Brewer Creek area reported a column test failure on the Nov 21 SH down 60cm. Several avalanches that occurred in the Toby Creek drainage last week are thought to have failed on the same layer. This is believed to be lurking around the Toby Creek drainage area, however data is sparse this early in the season and this layer is believed to extend to other areas.

The recent pounding from the atmospheric river delivered heavy precipitation, strong winds, and warm weather. Widespread natural avalanches were observed following each wave of the storm, up to size 3. Explosive control work throughout also produced storm slab avalanches to size 2.5.

10-40cm of low density snow sits over a supportive melt freeze crust, observed up to 2400m. Westerly winds have redistributed new snow into deeper deposits in wind loaded features at higher elevations.

A surface hoar layer extends throughout the Toby Creek drainage and surrounding areas - down 30 to 60 cm in sheltered features at treeline and below. Recent snowpack testing has shown this layer to produce sudden propagating fractures. We have limited knowledge of the distribution of this layer, but suspect is its most active between 1900-2400 m.  

A late October facet/crust layer of concern sits at the bottom of the snowpack above 1900m. This layer has been recently reactive to human and explosive triggers, and is reactive to snowpack tests. This layer is widespread throughout the region and will likely continue to be a layer of concern.

Average snowpack depth at treeline is 100-180cm, with the deepest snowpack found near the Bugaboos. 

• In times of uncertainty conservative terrain choices are our best defense.
• Be alert to conditions that change with elevation and wind exposure.
• Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
• Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.