New or lingering old windslabs may be found on steep N through E facing slopes, especially near ridge crests or behind other prominent terrain features. Continue to avoid these deep dense pillows of snow, particularly in common trigger spots like below droopy cornices, at the toe of a cliff, or on steep convex rolls and unsupported slopes.
Watch for wet avalanches at and below treeline on Thursday if the freezing level remains high and the rain continues to fall. If it’s getting wet near treeline or higher then avoid overhead hazard and stick to simple, gentle terrain. Avalanche danger should begin to drop by Thursday night as temperatures cool and precipitation tapers off.
A metre or more of snow has fallen in many areas at treeline over the past week; a couple of lingering shears are reported in this storm snow. Areas in the Purcells are reporting around 150cm at treeline and the Selkirks and Monashees are at about 200cm. In the Selkirks and Monashees the primary snowpack concerns are storm snow instabilities and locally deep pockets of wind slab. Below about 1800 – 2000m there’s a crust near the base of the snowpack in many areas that formed in October. In the Purcells, this crust has facets associated with it and it’s a concern in areas near Golden where it produced recent large explosive released avalanches and it sounds like it may have played a role in the incident noted in the Avalanche Activity section. So far the crust seems less of a problem in other areas, however this is not a certainty. Limited information means it’s difficult to provide specific information about the distribution, seriousness, and persistence of this layer.
A cold front moving southeast across the province is expected to stall over the northern part of the region this evening. This should cause the freezing level to drop to around 1200m near Revelstoke tonight but remain higher (16-1800m) in areas further south. Expect 5-15cm of snow tonight and another 10-15cm of snow on Thursday. The freezing level should drop to around 1000-1400m by Thursday evening. Precipitation should taper off on Friday and into the weekend and the freezing level should drop further to valley bottom.
There is a report of a close call west of Golden in the Purcells from November 22nd. Several people were caught in a human triggered avalanche in an east facing alpine bowl. Three riders were swept 150m downhill but managed to remain on the surface and escape unharmed
