Water Supply Outlook February 2013

Updated: February 7, 2013

Mountain runoff forecasts (natural volumes for March to September 2013)

Milk River basin
  • Average
Oldman River basin
  • Slightly below average for the St. Mary River and Oldman River at Brocket, average for Belly River and Oldman River at Lethbridge and above average for Waterton River
Bow River basin
  • Slightly below average for the Elbow River at Bragg Creek and Bow River at Banff,
  • Average for the Cascade and Spray Reservoirs, Highwood River at the Mouth, Kananaskis River at Kananaskis and Bow River at Calgary
Red Deer River basin
  • Average
North Saskatchewan River basin
  • Slightly below average for the Bighorn Reservoir
  • Average for the Brazeau Reservoir
  • Slightly below 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, 2013:

  • Oldman River basin: ranging from 45 to 120 % of normal
  • Bow River basin: ranging from 94 to 136% of normal
  • Red Deer, North Saskatchewan, Athabasca River basins: ranging from 88 to 107% of normal in the Athabasca River basin and ranging from 89 to 112% of normal in the North Sasakchewan River basin
  • Upper Peace River basin in British Columbia: 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 late-January in the Cypress Hills. 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, 2013 is shown here. The southern plains snowpack is indicated as near normal within a small pocket along the border as 50% of normal.
  • Alberta Agriculture publishes maps of modelled plains snow accumulations and accumulations as compared to normal.


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 January 27, 2013 is available here.

Long Lead Precipitation Outlooks

Environment Canada (issued on January 31, 2013): normal temperature for Alberta and normal precipitation for Alberta during the February to April 2013 period.

National Oceanic and Atmospheric Administration (NOAA) (issued on January 17, 2013): Below normal temperatures for southern Alberta and normal precipitation in southern Alberta, for February through April 2013.

Climate indicators: The NOAA reported on January 10, 2013 that neutral conditions are expected across the Nothern Hemisphere into Sping 2013.

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.


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

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