Heat warning issued as it could feel like nearly 40 C in southern Ontario

It could feel like nearly 40 C today in southern Ontario.

Environment and Climate Change Canada issued a heat warning as a hot and humid airmass is expected to arrive Wednesday and continue into Thursday in Ontario.

The warning includes Mississauga, Brampton, Halton Region the Niagara Region and Hamilton.

Maximum daytime temperatures of 30 to 32 C are expected, with humidex values near 40 C, the warning states.

There won’t be much relief overnight as minimum temperatures of 20 to 22 C are expected.

A cooler airmass may arrive by Thursday night, Environment Canada states.

Extreme heat can affect everyone’s health. The health risks are greater for older adults, infants and young children, pregnant people, people with physical and/or mental illnesses, and people with disabilities or mobility issues.

Drink plenty of water regularly, even before you feel thirsty to decrease your risk of dehydration, the warning suggests.

Thirst is not a good indicator of dehydration. Never leave people, particularly children, or pets inside a parked vehicle.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.