Water Supply Outlook February 2012

Updated: February 10, 2012

Mountain runoff forecasts (natural volumes for March to September 2012)

Milk River basin
  • Average
Oldman River basin
  • Below average for the St. Mary, Belly River, Waterton River, Oldman River at Brocket and Lethbridge
Bow River basin
  • Average for the Elbow River at Bragg Creek, Highwood River at the Mouth and Kananaskis River at Kananaskis
  • Above average for the Cascade and Spray Reservoirs
  • Above average for the Bow River at Calgary
  • Much above average for the Bow River at Banff
Red Deer River basin
  • Below average to average
North Saskatchewan River basin
  • Much above average for the Bighorn Reservoir
  • Above average for the Brazeau Reservoir
  • Average for the North Saskatchewan River at Edmonton

Precipitation can have a major impact on water supply between now and the end of September. The forecasts above assume that precipitation over the remainder of the winter period and through the summer will be normal. The range of possible precipitation scenarios is large however, and as a result, probable range forecasts and a minimal precipitation forecast of natural runoff volume are also provided for each individual basin. Since more information becomes known over time, forecast ranges will narrow. Streamflow volume forecasts are updated monthly from February to May, and again in July.

Check our Forecaster's Comments throughout the month for updated information regarding runoff conditions.

Mountain snowpack

Snow accumulations measured in the mountains as of February 1, 2012:

  • Oldman River basin: above average to much above average at most locations; average at Flattop Mountain, Lee Creek and Gardiner Creek stations.
  • Bow River basin: very consistent across the basin, above average to much above average
  • Red Deer, North Saskatchewan, Athabasca River basins: above to much above average in the Athabasca and Red Deer River basins, average to much above average in the North Saskatchewan River basin.
  • Upper Peace River basin in British Columbia: above normal, as indicated in British Columbia's Snowpack and Water Supply Outlook

Mountain snowpack is an important source of water supply to reservoirs in the spring. Accumulation at this time of year typically accounts for nearly two-thirds of the seasonal total.

Plains snowpack

  • Snow course measurements were taken in mid-January in the Cypress Hills, and values were below normal. The Cypress Hills snowpack is generally 70 to 90% of normal at the six snowcourse sites. Detailed information on plains area snowpack will be available in March as snow course measurements will be conducted near the start of the month.
  • Environment Canada map of satellite estimation of plains percent of normal snow water equivalent (SWE) as of February 1, 2012 is shown here. The southern plains snowpack is indicated as 50 to 70% of normal and some areas are snow free.
  • Alberta Agriculture publishes maps of modelled plains snow accumulations and accumulations as compared to normal.

Precipitation

Contoured maps of precipitation amounts and as a percent of normal for the past month and for current and recent seasons are available here. Maps of precipitation amounts for the most recent day, week and month to date are available here.

Soil Moisture

Alberta Agriculture models soil moisture for non-mountainous, agricultural areas of Alberta. Modelled soil moisture compared to average as of February 5, 2012 is available here.

Long Lead Precipitation Outlooks

Environment Canada (issued on January 31, 2012): above normal temperature in southern Alberta, and the eastern half of Alberta and normal temperature for the rest of the province and normal precipitation for Alberta, except below normal precipitation for south central Alberta, during the February to April 2012 period.

National Oceanic and Atmospheric Administration (NOAA) (issued on January 19, 2012): Normal temperatures and normal precipitation in southern Alberta, for February through April 2012.

Climate indicators: The NOAA reported on January 30, 2012 that La Nina conditions are expected to continue into Sping 2012.

Note that forecasting weather for such a long time period into the future is very difficult, and so the historical accuracy has been variable, dependent on location and time period, and is often low, more so for precipitation than temperature. Environment Canada provides an assessment of their forecast method's historical accuracy on their website.

Reservoir storage

Water storage volumes in the major irrigation and hydroelectric reservoirs of the Milk, Oldman, Bow, Red Deer North Saskatchewan, and Athabasca River basins is updated each weekday and is available in the Provincial Reservoir Storage Summary.

Questions

Background information on the Water Supply Outlook is available in Frequently Asked Questions

Media Contact:
Communications Division, Alberta Environment
Phone: (780) 427-6267