Two weather warnings issued in southern Ontario

Much of southern Ontario is under two weather warnings Monday.

The heat warning, which started on Friday and is expected to continue into Thursday, and the Greater Toronto Area is also under an air quality warning, according to Environment and Climate Change Canada.

It is expected to hit a high of 30 C on Monday but with the humidex, it could feel like 40 C in Mississauga, Toronto, Brampton, Hamilton, Halton and Durham Regions.

Daytime highs of 29 to 32 C and a humidex of 35 to 40 C are expected until Thursday. Overnight lows of 19 to 23 C are forecast, providing little relief from the heat, the warning states.

“Southern Ontario will experience hot and humid conditions now through much of this week,” the warning states. “A shift in the weather pattern late this week will likely end this multi-day period of heat and humidity Thursday night.”

People should watch for signs of heat stroke and check on older adults, those living alone.

Smoke from forest fires over northern Ontario has moved into southern Ontario, causing the air quality to deteriorate significantly, Environment Canada said in the warning.

The poor air quality may persist through the day and possibly into Tuesday for some areas.

People more likely to be impacted by wildfire smoke, including people aged 65 and older, pregnant people, infants and young children, people with an existing illness or chronic health condition, and people who work outdoors, should avoid strenuous activities outdoors and seek medical attention if experiencing symptoms, the warning states.

During heavy smoke conditions, everyone’s health is at risk regardless of their age or health status. Limit time outdoors. Reschedule or cancel outdoor sports, activities and events, the warning states.

Mild and common symptoms of poor air quality include eye, nose and throat irritation, headaches and a mild cough.

More serious but less common symptoms include wheezing, chest pains or severe cough.

When indoors, people should keep windows and doors closed as much as possible.

When there is an extreme heat event occurring with poor air quality, prioritize keeping cool. Protect indoor air from wildfire smoke. Actions can include using a clean, good-quality air filter in your ventilation system and/or a certified portable air cleaner that can filter fine particles.

“If you must spend time outdoors, limit the time as much as possible,” the warning states. “A well-constructed, well-fitting and properly worn respirator-type mask (such as a NIOSH-certified N95 or equivalent respirator) can reduce your exposure to the fine particles in the smoke.”

Areas in red are under heat warnings on Monday. Areas in the GTA area also under an air quality warning.