Canada: Water deficits in central QC & along QC/ON border

27 June 2017

The Big Picture
The 12-month outlook for Canada through February 2018 (below) indicates a band of exceptional deficits through the center of Quebec, in eastern Ontario, and in northeastern Manitoba along the Hudson Bay. Moderate to exceptional deficits are forecast in central and northwestern regions of Alberta and British Columbia.

Exceptional surpluses are forecast for central Manitoba west of Lake Winnipeg; a large block of northwestern Saskatchewan into Alberta; and southeastern British Columbia.

Impacts
The combination of saturated soil, heavy rain, and snowpack melt from unseasonably warm weather led to flooding in many parts of southern British Columbia during May. The water level on Okanagan Lake reached 343.06 meters on May 23, surpassing levels reached during the 1948 floods. Evacuation orders were issued for Central Okanagan, Similkameen, south of Vernon, and around the mouth of Mission Creek. A state of local emergency was declared around Trout Creek east of Highway 97 in Summerland due to the potential impact of rising ground water on the area's electrical system.

Though his winery was accessible, the mere warning of closed roads and washed out bridges in the Salmon River Valley scared potential visitors and was economically costly for a local vintner who depends on warm weather tourism.

Corn planting has been delayed in Quebec due to flooding in early May: planting in the province is 8 percent complete, considerably behind the 4 year average of 79 percent planted by mid-May. Overall, the country's 2017/2018 corn production is forecast to be down 9 percent from last year.

In early June burning permits were canceled in central and eastern Manitoba due to increased wildfire risk from hot, dry, and windy conditions. Water use restrictions were in place for about 20,000 water consumers in southern Manitoba.

Forecast Breakdown
The 3-month maps (below) show the evolving conditions in more detail.

In general, conditions are expected to become less extreme with longer lead times (September through February), with near normal conditions for much of Ontario, Quebec, and the Maritimes. However moderate drought conditions persist in northern British Columbia, northern Manitoba, and northwest Ontario. Much smaller pockets of exceptional surpluses persist in central Manitoba west of Lake Winnipeg; northwestern Saskatchewan into Alberta; and southeastern British Columbia.

(It should be noted that forecast skill declines with longer lead times.)