News » Whistler

Backcountry Advisory

comment

As of Wednesday, April 4

Snow conditions in the mountains during the past week have been some of the most enjoyable of the winter – cool temperatures, power flurries, and periods of clearing. An added bonus is the fact that the deep weaknesses that plagued us in the snowpack throughout the winter are in many areas becoming bridged over by melt-freeze crusts.

In the Whistler corridor there has been no reported activity on either the November facet layer or the February surface hoar layer since the monsoon/windstorm of March 25. The wet snow created by this storm formed a variable crust that has since been buried by subsequent snowfalls. Depending on aspect and elevation, warming and solar effect may have caused the formation of additional crusts. On north aspects above about 2,000m., the crust becomes weaker and eventually disappears. Without the solid overlying bridge, any rocky, low snowpack terrain should still be approached with caution. Keep in mind that the bridging effect created by a crust will decrease as the crust loses strength. Extended warm temperatures or rain percolating into the snowpack will rapidly change the snow stability.

Any backcountry enthusiast is aware that at this time of year, aspect and elevation play a critical role, particularly if the sun makes even a brief appearance. Snow quality becomes highly variable, and timing your day sometimes turns into a bit of a challenge. Consequently, the new snowfall is also landing on a huge variety of old surfaces – some may allow for a good bond, while others may not. It becomes increasingly important to do your snow tests in areas that accurately represent the terrain in which you intend to play. Pay particular attention to the crust interfaces, looking for any signs of weaknesses.

The long-range forecast is calling for a cool north-westerly flow to provide us with periods of snowfall through the end of the week and into the weekend.

As of April 4, the backcountry avalanche danger is rated as MODERATE. Conditions may vary and can change rapidly, so try to obtain the most current information before you head out.

Add a comment