Spring 2012 Conditions


Spring 2012 Traverse Conditions

 April 6th 2012

Traverse season has started in the mountains of western Canada and adventurous parties are gearing up to take advantage of the longer days and generally more favourable conditions that spring-time travel offers. Whether you’re from BC trying to do a little more exploration of your own “backyard”, or whether you’re from further afield and looking for a true Canadian wilderness adventure, you’ll appreciate some resources to help figure out what conditions may be like on routes you’re considering.

The map below shows regional snow water amounts (a good surrogate for snowpack depths) as a percentage of normal values and is provided by the BC River Forecast Centre. It is updated monthly at the beginning of each month—check here for the most recent report. You should also check the automated snow pillow site, which provides more detailed information on snow cover for specific drainages, including values of actual (rather than relative) snow depths.

View larger image Snow water amounts for major river basins of BC. BC River Forecast Centre.

Regional overview

Most areas this year are showing higher than average snow depths. In the south, coastal regions as well as the eastern Selkirks and the Purcells are showing higher than average snow depths, while the western Selkirks and Monashees are closer to seasonal norms. Further north, there is a band of particularly high snow depths stretching along the central and northern coast from the Knight Inlet to just north of Stewart and inland encompassing the north Rockies and parts of the Cariboos from Prince George to Valemount. Some drainages in this area have exceptionally high snow depths. For example, the Nechako drainage east of Kitimat was showing 165% of normal snow depths as of 01-April-2012. Further north still, snow depths are more in line with seasonal norms.

Regional snow depths provide information for helping to plan access as well as determining whether there is sufficient snow cover for travel on skis. Factors to consider for access include whether logging roads are passable or whether snowmobile access is possible. Factors associated with travel on skis include anticipating whether glaciers have sufficient snow cover for crevasses to be bridged, whether low-lying valleys are skiable, whether lakes are frozen, and whether egress is possible at the end of the trip.

The sections listed in the menu on the left provide general information about snowpack and avalanche conditions for certain popular traverse regions. This information is intended to give people planning a traverse this season an idea of the nature of recent avalanche problems. Additionally, you can check through the CAC's weekly summaries of weather, snowpack and avalanche activity. These are listed here, and will help you identify major snowpack features.

Please note, this information is presented as guidance for planning purposes only and is not intended to be used in the field to make day-to-day slope-scale decisions. It will be necessary to make your own assessment of whether a trip is suitable given the conditions at the time of travel and the experience level of your group. Constant observations and snowpack stability assessments when on the traverse are imperative.

Above all, remember that winter persists far longer above treeline and snow continues to accumulate in the mountains, well into May or even beyond. It’s common to see new snow instabilities, wind slabs and cornice growth, as well as wet slabs, loose wet avalanches and other warming-related instabilities.