Environment Canada is warning of poor air quality and extreme heat in Toronto on Monday as southern Ontario braces for a week filled with hot and humid weather.

In Canada, the Air Quality Health Index (AQHI) is a scale developed to help people understand what the current air quality means for your health. It is an initiative among Environment Canada, Health Canada and the provincial governments.

The poor air quality that has blanketed swaths of central and Western Canada is not only infiltrating the lungs, but also distressing the mind.

There’s a layer of haze in the air, as smoke from burning wildfires has blown into southern Ontario. And according to the World Air Quality Index website, Toronto is one of the worst places in the world right now for air quality.

While some organizations have published clear air quality thresholds or contingency protocols for wildfire smoke, FIFA's plans remain unclear less than a year out from the 2026 World Cup.

Expect deteriorating air quality across parts of Ontario heading into the new workweek as upper-level winds blow wildfire smoke into the region. Some of the smoke could mix down to the surface, lowering air quality from northern Ontario to the Greater Toronto Area.