Canada swelters under extreme heat as wildfire smoke chokes skies, prompting nationwide health alert

Environment Canada has issued hundreds of heat and air quality warnings as scorching temperatures and thick wildfire smoke affect communities across the country this weekend.

Daytime highs above 30°C (86°F) are forecast for parts of Ontario, Quebec, Newfoundland and Labrador, and the Northwest Territories, with humidex values reaching 35-40°C. Nighttime temperatures will remain unusually warm, just above 20°C, preventing homes from cooling down overnight.

The agency warns the prolonged heat poses health risks to everyone, with seniors, infants, outdoor workers, and people with chronic conditions especially vulnerable. Symptoms of heat exhaustion include dizziness, nausea, and fatigue, while heat stroke can cause confusion, red and hot skin, and loss of consciousness.


Officials advise drinking water regularly, staying in shaded or air-conditioned spaces, and scheduling outdoor activities for cooler parts of the day. “Never leave people or pets inside a parked vehicle,” the agency stresses.

Smoke from Canada’s record wildfire season worsens air quality

Heavy smoke from 715 active wildfires, mainly in the northern Prairies, is reducing visibility and triggering air quality alerts in Alberta, Saskatchewan, Manitoba, the Northwest Territories, New Brunswick, and Newfoundland and Labrador.

This year’s blazes have already burned 72,000 square kilometers, the second-worst wildfire season on record, behind 2023.

Poor air quality is particularly dangerous for young children, pregnant people, older adults, and those with heart or lung conditions. Residents are urged to keep windows and doors closed, use clean air filters, and limit strenuous outdoor activity.

Rainfall warnings in the west

Meanwhile, British Columbia, Manitoba, and Saskatchewan are under rainfall warnings, with heavy downpours expected to continue through Sunday, raising the risk of flash floods and poor driving visibility.