Eastern Ontario and Western Quebec face prolonged heat wave
A prolonged stretch of hot, humid weather has triggered a heat warning across much of Eastern Ontario, including Ottawa, Kingston, Cornwall, and neighbouring Gatineau in Western Quebec. Issued by Environment Canada late Friday morning, the warning could remain in effect until Thursday, July 17, depending on how the conditions evolve.
Temperatures soaring, humidex near 40
Daytime highs are forecasted to sit between 29 and 32 °C (84 to 90 °F) through much of the week. But when humidity is factored in, it could feel closer to 40 °C (104 °F). Nighttime lows will likely hover around 20 °C (68 °F) or higher, offering little relief from the heat overnight.
Saturday is shaping up to be the most intense day in this stretch. Ottawa is expected to reach a high of 31 °C (88 °F), with overnight temperatures dipping only to 22 °C (72 °F) — all while humidity continues to blanket the region.
Different areas, different impacts
While the warning covers a wide swath of Eastern Ontario, it does not extend to Renfrew County, Prince Edward County, or the Bancroft area. Over in Western Quebec, Grenville-sur-la-Rouge is also under a heat warning, though conditions there may ease by Monday. Other parts of Western Quebec remain under a special weather statement, with slightly milder temperatures forecast for Friday and Saturday.
Sticky nights, heavy air, rising risk
What makes this heat event particularly uncomfortable is the persistently high humidity and overnight temperatures that barely dip below 20 degrees. Without the usual nighttime cooling, buildings retain heat, putting added pressure on people, particularly the elderly and those with pre-existing health conditions.
There’s growing concern among health officials about prolonged exposure to extreme heat. Environment Canada is urging residents to monitor for signs of heat-related illness — symptoms like headaches, dizziness, or a racing heartbeat — and to take them seriously. Heat stroke, marked by confusion, flushed skin, or loss of consciousness, is a medical emergency.
Cities respond with local support
Municipalities such as Ottawa have rolled out public resources to help residents cope. A map of available cooling centres is now online, and community centres and libraries are among the spaces offering relief. While there’s some indication that temperatures could start to ease by late next week, forecasts remain uncertain the further out they go.
For now, the message is clear: the heat is here to stay, at least for the coming days.
