Water Supply Outlook August 2017
Updated: August 11, 2017
Mountain runoff forecasts (natural volumes for March to September 2017)
Milk River basin- Much below average to above average for the March to September 2017 period
- Much below average for August to September
- March-July recorded volumes are much below average to much above average
- Below average to much above average for the March to September 2017 period
- Below average to much below average for August to September
- March-July recorded volumes are average
- Below average to much above average for the March to September 2017 period
- Below average to above average for August to September
- March-July recorded volumes are below average to above average
- Average to above average for the March to September 2017 period
- Average for August to September
- March-July recorded volumes are below average to above average
- Below average to much above average for the March to September 2017 period
- Below average to much above average for August to September
- March-July recorded volumes are much below average to above average
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 (issued in December to June each year)
Plains Spring Snowmelt Runoff Forecasts (issued in March and April each year)
Plains Snowpack (issued in March and April each year; Cypress Hills mid to late January and February)
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 relative to long term normal as of August 7, 2017 is available here.
Long Lead Precipitation Outlooks
Environment Canada (issued on July 31, 2017): Temperature is forecast to be above normal for the August through October 2017 period, for the entire province. Precipitation is forecast to be below normal for the August through October 2017 period across most of Alberta.
National Oceanic and Atmospheric Administration (NOAA) (issued on July 20, 2017): An equal chance of below normal, normal or above normal precipitation in southern Alberta for August through October 2017. Above normal temperature in southern of Alberta for August through October 2017.
Climate indicators : The NOAA reported on August 10, 2017 that ENSO-neutral is favored (~85% chance during Jul-Sep, decreasing to ~55% during Dec-Feb) through the Northern Hemisphere winter 2017-18.
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 and Parks
Phone: (780) 427-8636
