Health Department advises residents to prepare for potential heat event this weekend

Whitby, Ontario – Forecasted temperatures for this upcoming weekend are expected to meet the criteria for a heat warning in both north and south Durham Region. This is the first heat event of 2025 under Durham Region Health Department’s seasonal Heat Warning and Information System. This is expected to be a multi-day heat event, possibly continuing into next week.

Everyone is encouraged to stay alert and take precautions; remember to visit neighbours, friends and older family members – especially those who are chronically ill, living alone or without air conditioning – to ensure that they are staying cool and hydrated.

Never leave infants and young children inside a parked vehicle. This is especially important when the outside air temperature is 23ºC/73ºF, as the temperature inside a vehicle can be extremely dangerous and can reach more than 50ºC/122ºF very quickly. Call 911 immediately if you see a child left unattended in a vehicle.

Throughout the summer, the Health Department will be posting information at durham.ca/Heat to inform residents when heat alerts are issued and share resources to help them stay cool. The Health Department will also provide updates through social media. Follow us on Facebook, X, and Instagram.

A heat warning is issued when the Environment and Climate Change Canada forecast includes a daytime high of at least 31°C and overnight temperatures of 20°C or greater, or with humidex (humidity index) values of at least 40 for two or more days. The humidex value describes how hot the weather feels to the average person, by combining the effect of heat and humidity.

The Health Department advises residents to take precautions to prevent heat-related illness, and has resources such as, Heat Hacks for Keeping Cool, to help you plan ahead and prepare for extreme heat events. Extreme heat can be harmful to everyone; health risks are greatest for infants and young children and people who are age 60 or older, as well as individuals who are pregnant, live alone, take certain medications, lack secure housing, have an existing health condition, have limited resources, have limited physical mobility or work or exercise outside. Those who take medication or have a health condition should ask their doctor or pharmacist if these can increase their health risk in the heat and follow appropriate recommendations.

Heat-related illnesses are preventable. If symptoms of heat-related illness are observed, immediately move the person to a cool place, provide water, and apply damp towels to their body. Symptoms to watch for include:

• Dizziness or fainting
• Swelling of hands, feet or ankles
• Nausea or vomiting
• Headache
• Fast breathing and heartbeat
• Extreme thirst or fatigue
• Changes in behaviour (sleepiness or temper tantrums in children).

The most dangerous heat-related illness is heatstroke, which is a medical emergency. Symptoms include complete or partial loss of consciousness, confusion and high body temperature above 39°C or 102°F. If caring for someone with these symptoms, call 911 immediately. While waiting for help, move the person to a cool area, place wet towels, clothing or icepacks around the body, focusing on the neck, armpits, and groin areas.

The following precautions are recommended to beat the heat and stay cool:

• Drink water regularly. Don't wait to feel thirsty.
• Layer damp towels on body or mist with water.
• Take cool showers or place feet in cool water.
• Rest and limit physical activity.
• Take a break from the heat by spending a few hours in a cool place.
• Block out the sun by opening awnings and closing curtains or blinds during the day.
• Avoid sun exposure. Shade yourself by wearing a wide-brimmed, breathable hat or using an umbrella.
• Reschedule or plan outdoor activities during cooler parts of the day.
• If the night is cooler, open windows to cool home.
• Never leave people or pets inside a parked vehicle.

Stay up to date on news and updates from Environment and Climate Change Canada. For more information about the Health Department’s Heat Warning and Information System, as well as more tips on how to stay safe and what to do during extreme heat, visit durham.ca/Heat, or contact Durham Health Connection Line at 905-668-2020 or 1-800-841-2729.

- 30 -

For more information, please contact the Health Department.