Mountain Snowpack

Snow accumulations in the mountains as of February 1, 2007 are generally below average to average in the Waterton, St. Mary and Belly River basins, average in the Oldman and Elbow River basins, average to above average in the Highwood River basin, above to much above average in the Kananaskis, North Saskatchewan and Red Deer River basins, and much above average in the Athabasca and upper Bow River basins (Table 1). The mountain snowpack is an important source of water supply to reservoirs in the spring. On average, the accumulation of snow at this time of the year accounts for nearly two-thirds of the seasonal total.

Eight snow courses and two automated snow pillow readings were taken at the end of January in the Oldman River Basin, with values ranging from 77 to 108% of average. Generally the snowpack is average in the Oldman River basin, however the two US stations, in the upper Belly and St. Mary River basins, are below average (Table 2).

Eighteen snow courses were measured at the end of January in the Bow River Basin, with values ranging from 91 to 162% of average (Table 3). Snow accumulations are generally much above average in the upper Bow River basin, above to much above average in the Kananaskis River basin, average to above average in the Highwood River basin and average in the Elbow River basin. Snow courses are generally much higher than at this time last year, and in the Kananaskis and upper Bow River basins rank 3^rd to 7^th highest in generally 25-40 years of record.

One snow course was measured in the Red Deer River basin indicating the snowpack is 144% of average as of February 1, 2007, which is much above average for this time of year (Table 4). A snow course at Limestone, which is on the watershed divide of the Red Deer and North Saskatchewan River basins, is 115% of average which is above average. Measured values are much higher than those observed in 2006.

Two snow courses were measured in each of the upper North Saskatchewan River and Athabasca River basins at the end of January. The values were 132 and 148% of average (much above average) in the Athabasca River Basin and 115 and 156% in the upper North Saskatchewan River Basin, which is above to much above average for this time of year. Measured values are much higher than those observed in 2006.

Snow course measurements in the upper Peace River basin in British Columbia indicate snowpacks are well above normal for this time of year, as seen in British Columbia's Snowpack and Water Supply Outlook: http://www.env.gov.bc.ca/rfc/river_forecast/bulletin.htm.

At twelve snow course sites, real-time snow accumulation can be monitored using snow pillows. Snow pillows can be viewed by choosing any mountainous southern basin, and snow data, in the two drop down menus at:

Snow water equivalent values on the snow pillow may or may not match the snow course value at a particular location. While snow pillow data is very valuable information, the quantity of snow on the pillow is only representative of the accumulation at that specific spot. A snow course survey is measured at numerous spots and provides a more representative value of snow in the area. In some locations, there can be considerable difference between the snow pillow and snow course values. Factors such as wind and exposure of the site can cause the snow pillow values to be significantly different from the snow course survey. The snow pillow graphs on our website show the daily average snow water equivalent. The monthly snow survey is the average of all measurements conducted within five days of the end of the month. Also, where snow pillow and snow course measurements are available for the same site, snow pillow records tend to be much shorter (10-15 years) in length compared to the snow course sites. As a result, the difference in the average value between the snow pillow and the snow course can be attributed to snow water equivalent being derived two different ways (physically measured compared to an instrument reading), site location and length of data record. In some cases, the values can deviate by 10-20%. Therefore, while snow pillows are excellent for analyzing trends and for monitoring accumulation between snow surveys, snow course values should always be used when considering the quantity of snow at a particular location as they best represent that area.

Click here to see a map of snow course locations

Plains Snowpack