A large heat dome forecast to build over the western United States this weekend is expected to move into parts of western Canada, bringing several days of unusually hot weather.
The pattern is also raising concerns about wildfire risk across the Prairies, especially in areas already dealing with dry conditions.
High-Pressure System to Push Temperatures Higher
A broad area of high pressure is expected to form during one of the hottest times of the year in the United States.
This system is forecast to send temperatures far above seasonal averages across parts of the Rockies and northern Plains before spreading north into Canada.
Retired Environment Canada senior climatologist David Phillips told CTVNews.ca that Canadians have already seen how this kind of weather setup can move beyond the U.S. border.
He compared the pattern to placing a lid over a wide region, trapping heat over the western United States before allowing it to spill into Canada.
Southern Prairies Expected to Feel Strongest Heat
Phillips said communities in the southern Prairies are likely to experience the strongest effects.
He noted that many Prairie areas have not seen a long stretch of hot weather since a short warm period in late May.
According to Phillips, next week could bring plenty of sunshine and warmer-than-normal temperatures.
Some areas may see temperatures five to seven degrees above seasonal levels, while a few places could reach nearly 10 degrees warmer than usual for this time of year.
Heat Pattern Shifts From East to West
The coming heat follows an early July warm spell that affected parts of Ontario, Quebec and Atlantic Canada before the pattern began shifting west.
Chief meteorologist Kelsey McEwen told CTVNews.ca that Canada’s July weather pattern is about to change sharply.
She said the eastern half of the country began the month with hot weather, while western Canada saw cooler-than-average temperatures. That setup is now expected to reverse as the country moves toward mid-July.
Same System to Influence Canada
McEwen said the high-pressure system responsible for the U.S. heat will also affect Canadian weather.
She explained that weather systems do not stop at international borders, meaning the same high pressure will settle over western Canada.
The system is expected to push the jet stream farther north, allowing hot air to build over Alberta and parts of Saskatchewan.
At the same time, parts of Northern Ontario may experience cooler-than-normal conditions.
Wildfire Concerns Increase
McEwen warned that a longer period of hot and dry weather could make wildfire conditions worse in areas already facing active fires.
High pressure causes air to sink, which can increase temperatures even more.
It also limits cloud formation and reduces the chance of rain.
McEwen said this becomes a problem for regions that are already dry, because heat and a lack of rainfall can create more difficult wildfire conditions.
First Sustained Summer Heat for Some Areas
For some western Canadian communities, the expected heat may be the first extended period of truly summer-like temperatures this season.
That sudden change could increase health risks, especially for vulnerable people.
Heat Safety Advice
Health officials generally recommend taking precautions during extreme or prolonged heat.
People are advised to drink enough water, avoid heavy outdoor activity during the hottest hours, stay in shaded or air-conditioned places when possible, and check on older adults, young children and others more vulnerable to heat stress.
Canadians can follow the latest watches and warnings through Environment and Climate Change Canada weather alerts.
A developing heat dome over the western United States is expected to extend into western Canada, bringing several days of above-normal temperatures. The southern Prairies are likely to feel the strongest effects, with parts of Alberta and Saskatchewan expected to see prolonged heat.
The dry and hot pattern may also worsen wildfire concerns, making it important for residents to monitor weather alerts and take heat-safety precautions.