Water Supply Outlook November 2012
Updated: November 14, 2012
Recorded natural runoff volumes from March to September 2012
Natural runoff volumes from March to September 2012 were generally average to above average in the Bow river, Red Deer River and North Saskatchewan River basins, average in the Oldman River basin and slightly below average in the Milk River basin.
Natural runoff volumes recorded from March to September 2012 for most of the rivers in the Oldman River, Bow River, Red Deer River and North Saskatchewan River Basins ranked from 51 to 90th highest in 91 years of record. However, the Waterton River reached only the 28th highest in 91 years of record. Lake Abraham Inflow and Brazeau Reservoir Inflow ranked from 29 to 33rd highest in 30 and 41 years of record respectively. The Milk river at Eastern Crossing and Milk River at Milk River recorded 35 and 40th highest in 91 years of record. The Milk River at Western Crossing recorded 34th highest in 70 years of records.
The average difference between forecast and recorded natural volumes were 5 to 11% for the Milk River, Oldman River, North Saskatchewan River basins and 18% for the Bow River and Red Deer River basins.
Milk River basin- March - September recorded volumes slightly below average for the Milk River due to slightly below normal precipitation along the Canada/U.S. border in southern Alberta this summer.
- Five months forecasts (January to May) issued for 3 locations were on average, accurate within 5%. Runoff was slightly below average.
- March - September recorded volumes average for the St. Mary River, Belly River and Oldman River except for the Waterton River where it is slightly below average.
- Five months forecasts (February to May and August) issued for 5 locations were on average, accurate within 11%. Runoff was generally average except for the Waterton River.
- March - September recorded volumes average to above average for the Bow River, Spray River, Kananaskis River, Elbow River and Highwood River except for Lake Minnewanka Inflow which is much above average.
- Five months forecasts (February to May and August) issued for 7 locations were on average, accurate within 18%. Runoff was generally average to above average except for Lake Minnewanka Inflow.
- March - September recorded volumes average to above average for the Red Deer River at Dickson Dam and City of Red Deer.
- Five months forecasts (February to May and August) issued for 2 locations were on average, accurate within 18%. Runoff was average to above average.
- March - September recorded volumes average to above average for Lake Abraham inflow, Brazeau Reservoir inflow and North Saskatchewan River at Edmonton.
- Five months forecasts (February to May and August) issued for 3 locations were on average, accurate within 7%. Runoff was average to above average.
Note: The recorded 2012 natural flow volumes are preliminary and subject to change.
Check our Forecaster's Comments for updated information regarding runoff conditions.
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 October 31, 2012 is available here.
Long Lead Precipitation Outlooks
Environment Canada (issued on October 31, 2012): temperature and precipitation for the November 2012 through January 2013 period:
- above normal precipitation in southern and central Alberta. Normal precipitation in northern Alberta.
- normal temperatures throughout the entire province.
National Oceanic and Atmospheric Administration (NOAA) (issued on October 18, 2012): normal precipitation and slightly above normal temperature for southern Alberta for November 2012 through January 2013.
Climate indicators: The NOAA reported on October 4, 2012 that borderline neutral/weak El Nino conditions are expected to continue across the Northern Hemisphere during the winter of 2012 - 2013, possibly strengthening in the next few months.
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
