Environment Canada has issued an extreme heat warning for Ottawa on Canada Day, July 1, 2026, with temperatures forecast to reach 35°C and humidex values making it feel like 40°C. The warning, issued early Tuesday morning, covers the Ottawa-Gatineau region and is expected to persist through the holiday weekend.
Heat wave conditions and health risks
The heat warning comes as southern Ontario experiences its first heat wave of the summer. Meteorologists warn that duration, not intensity, is the primary danger, with prolonged exposure leading to heat exhaustion or heat stroke. The city has opened cooling centres at various locations, including community centres and libraries, to provide relief for residents without air conditioning.
According to Ottawa Public Health, vulnerable populations such as the elderly, young children, and those with chronic illnesses are at higher risk. Officials advise staying hydrated, limiting outdoor activities during peak heat hours (11 a.m. to 4 p.m.), and checking on neighbours.
Canada Day festivities proceed with precautions
Despite the heat, Canada Day celebrations are ongoing, including fireworks displays at designated sites. Organizers have set up misting stations and water distribution points at major event venues. The city reminds attendees to wear light clothing, apply sunscreen, and seek shade frequently.
"We want everyone to enjoy Canada Day safely," said a city spokesperson. "Please take the heat warning seriously and plan accordingly."
Regional impact and response
The extreme heat warning extends to other parts of eastern Ontario and western Quebec. Hydro One has reported increased demand on the power grid, urging conservation to avoid outages. Cooling centres are also open in Gatineau, with extended hours on Canada Day.
Environment Canada meteorologist Peter Kimbell noted that the heat wave is caused by a stagnant ridge of high pressure. "It's not just the high temperatures but the lack of overnight cooling that poses a health risk," he said.
Residents are advised to monitor local weather alerts and visit the city's website for a full list of cooling centre locations and hours.
