Avalanche Forecast

TUESDAY NIGHT: Partly cloudy, light northwest wind, freezing level valley bottom.

WEDNESDAY: Sunny, light to moderate southwest wind increasing in the evening, freezing level 1000 m.

THURSDAY: 5-10 cm new snow, strong southwest ridgetop wind, freezing level 1000 m.

FRIDAY: 5-10 cm new snow, moderate westerly ridgetop wind, freezing level valley bottom.

Reporting since the storm has been limited to the Valemount area, which received lowest snowfall in the region. Numerous natural storm slabs up to size size 2 have been observed on a variety of aspects, as well as a machine triggered size 2.5.

Recent snowfall amounts have been in excess of 100 cm in the south of the region near Blue River and north of McBride, and 40-50 cm Barkerville to Valemount. At upper elevations, all of this recent snow has likely been blown around by strong to extreme westerly winds, forming thick, reactive slabs in lee features. At lower elevations, the new snow is likely settling in the mild temperatures.

The recent snow sits on old, facetted and/or extensively wind affected snow that sat on the surface during the extended cold, windy drought period. There is uncertainty around how long it will take for this interface to bond but reports from the Monashees in the neighboring North Columbia region have indicated a positive trend already.

We've now got 80-180 cm of snow above the early February persistent weak layer which is composed of surface hoar. This layer is most prevalent at treeline and in "treeline-like" features like cutblocks. On steep south-facing terrain, this layer may consist of facets on a sun crust. We are awaiting reports of avalanche activity during the storm, specifically whether they indicate step- downs to this layer, to determine whether or not it continues to be a problem.

• Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
• Start with simple well supported terrain below treeline and gather information before stepping out.
• Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.