Extreme heat
Extremely high humidity can be hazardous to your health. Check in on your neighbours on hot days.
Extreme heat events involve high temperatures and sometimes high humidity. Although the level of temperature extremes may vary between regions, high heat can negatively impact your health.
What are the dangers of hot weather?
Extreme heat can put your health at risk, causing heat stroke, dehydration and even death. It is important to protect yourself and your family. With hot weather usually comes bright sunshine, and potentially poor air quality.
What is the humidex?
High humidity can cause the air temperature to feel hotter than it actually is. That’s because when people sweat to cool down, this perspiration cannot evaporate as easily in moist, saturated air. The Government Canada calculates and publishes the humidex reading to let people know how hot it feels with the humidity.
What is Public Health Sudbury & Districts role on hot days?
Public Health Sudbury & Districts is responsible for declaring heat advisories, heat alerts, and extreme heat alerts under the City of Greater Sudbury Hot Weather Response Plan. These alerts notify the public of extreme heat warnings, with additional response from the City depending on the alert level.
Who is at risk?
Even healthy people and pets can get sick because of hot weather. The following groups are at higher risk and need to be sun safe:
- older adults
- people with chronic illnesses or conditions (such as heart or breathing conditions, people with limited physical mobility and people with certain mental health illnesses)
- babies and young children
- pregnant people
- people who work or exercise outdoors
- people taking certain medications
- people who use alcohol or illicit drugs
- homeless people
- low-income earners
High heat and humidity can also be a threat if you live in a building that does not have adequate cooling.
What should I do before an extreme heat event?
To prepare for an extreme heat event, you should:
- Build an emergency kit and make a family communications plan.
- Install window air conditioners snugly; insulate if necessary.
- Check air-conditioning ducts for proper insulation.
- Install temporary window reflectors (for use between windows and drapes), such as aluminum foil-covered cardboard, to reflect heat back outside.
- Weather-strip doors and sills to keep cool air in.
- Cover windows that receive morning or afternoon sun with drapes, shades, awnings, or louvers. (Outdoor awnings or louvers can reduce the heat that enters a home by up to 80%.)
- Listen to local weather forecasts and stay aware of upcoming temperature changes.
- Know those in your neighbourhood who are at higher risk of heat-related illness so that you can check-in on them during hot days.
- Be aware that people living in urban areas may be at greater risk from the effects of a prolonged heat wave than are people living in rural areas.
- Get trained in first aid to learn how to treat heat-related emergencies.
What should I do during an extreme heat event?
- Tune in to local TV or radio channels for emergency advisories and instructions.
- Check the weather information regarding weather and humidex reports (Government of Canada).
- Check the Ministry of the Environment, Conservation and Parks website for information regarding smog alerts.
- Drink lots of water, even if you don’t feel thirsty.
- Avoid alcoholic or caffeinated drinks.
- Limit the time you spend outdoors during the hottest part of the day.
- Go to air-conditioned or cooler places like shopping malls, libraries, community centres, or a friend’s place.
- Stay on the lowest accessible floor of your home or building, and stay out of the sunshine if air conditioning is not available.
- Keep shades or drapes drawn and blinds closed on the sunny side of your home, but keep windows slightly open if you don’t have air conditioning.
- Keep electric lights off or turned down low.
- Take a cool bath or shower, or cool down with cool, wet towels.
- Avoid using your oven.
- Avoid intense or moderately intense physical activity.
- Fans may not cool enough when the temperature is high, as they just move the air around.
- Check on family, friends, and neighbours who do not have air conditioning and who spend much of their time alone.
- Check on your pets frequently to ensure that they are not suffering from the heat.
For more information on extreme heat or to speak to a public health inspector call 705.522.9200 or toll-free at 1.866.522.9200.
This item was last modified on July 7, 2022