Active Alerts Kilsyth, ON

Heat Warning
Issued at Thu 11:37 PM Jun. 20
Issued by: Environment and Climate Change Canada

A prolonged heat event continues through Friday. Dangerously hot and humid conditions are expected.

Daytime highs are expected to be 29 to 32 degrees Celsius with humidex values of 38 to 42. There will be little relief through the overnight as lows are expected to be 20 to 23 degrees Celsius with humidex values of 26 to 30. Temperatures and humidex values may be several degrees cooler near the shores of the Great Lakes.

Less hot and humid conditions are expected to slowly move into the area this weekend. Daytime highs are expected to be in the 28 to 31 degree Celsius range with overnight lows of 18 to 22 degrees Celsius. There is some uncertainty regarding how quick this cooler and drier airmass will move in so heat warnings may persist through the weekend.

Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high risk category.

Drink plenty of water regularly, even before you feel thirsty to decrease your risk of dehydration. Thirst is not a good indicator of dehydration.

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.

Never leave people, particularly children, or pets inside a parked vehicle.

Watch for the effects of heat illness: swelling, rash, cramps, fainting, heat exhaustion, heat stroke and the worsening of some health conditions.

Heat stroke is a medical emergency! Call 911 or your local emergency number immediately if you or someone you are caring for has a high body temperature and is confused, has stopped sweating or becomes unconscious.

While waiting for help, cool the person right away: move them to a cool place, apply cold water to large areas of the skin and fan the person as much as possible.


Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to or tweet reports using #ONStorm.