The Medical Officer of Health will issue an Extreme Cold Weather Alert when Environment Canada forecasts a temperature of -15° C or colder, or a wind chill of -20° C or colder, for the city of Toronto.

Extreme Cold Weather Alerts may also be issued when the forecast includes factors that increase the impact of cold weather on health. These include precipitation, low daytime temperatures, or several days and nights of cold weather in a row. The Cold Weather Response Plan provides a framework for implementing and co-ordinating cold weather preparedness and response activities which focus on reducing the negative health impacts of cold weather conditions.

To find out total days and dates that extreme cold weather alerts were issued in Toronto for winter seasons going back to 2004-2005, visit Statistics on Extreme Cold Weather Alerts in Toronto.

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The personal information on this form is collected under the authority of the City of Toronto Act, 2006 and the Health Protection and Promotion Act, R.S.O. 1990, c. H.7. The information is used to subscribe the provided email address to a City of Toronto e-notice for cold weather alerts. Questions about this collection may be directed to the Manager, Healthy Environments, Toronto Public Health, 5100 Yonge St., 2nd floor, Toronto, ON M2N 5V7. Telephone: 416-338-7600. By subscribing to this service you are providing express consent, as defined by the Canadian Anti-Spam Legislation (CASL), to receive email updates from the City of Toronto.

Exposure to extreme cold weather can be harmful to your health. Follow these tips to stay warm, dry and healthy this winter.

Check on Family, Friends & Neighbours

During extreme cold weather conditions, please check (e.g., call, videocall, text, etc.) on vulnerable family, friends and neighbours, especially isolated seniors. If no answer is received, consider knocking on their door to check in on them.

People at risk for cold-related illnesses include:

  • people with pre-existing heart conditions or chronic respiratory illness
  • infants and young children
  • people on certain medications
  • people who work or do physical activities outside for extended periods
  • people who are marginally housed or homeless

To protect yourself from cold-related illnesses:

Dress in Layers and Cover Exposed Skin

  • Cover as much exposed skin as possible. Frostbite can develop over a relatively short period of time during periods of extreme cold.
  • Wear waterproof and windproof outer layers.
  • Wear a hat.
  • Choose warm mittens instead of gloves.
  • Wear warm, waterproof boots.
  • Choose wool, silk or polypropylene inner layers of clothing, these materials hold more body heat than cotton.

Stay Dry

  • Avoid wearing wet clothing, as you are more likely to develop hypothermia if you are cold and wet.
  • Change into dry clothing as soon as possible if you get wet from precipitation, sweat or submersion in water.

 Take Care When Outdoors

  • Check the weather report before going outside.
  • Warm up by taking regular breaks in heated buildings such as libraries and malls.
  • Reschedule outdoor activities and limit time outdoors if severe weather is forecast.

Stay Active and Safe

  • Wear comfortable winter boots with a wide and low heel.
  • Wear bright-coloured clothing in snowy weather.
  • Notify friends or family where you will be when going on outdoor activities, such as hiking and skiing.

Read more about cold-related illness and how to stay warm and healthy this winter.

Plan ahead and get your home and car ready for winter:

  • Heat your home to 21° C.
    • For renters: Toronto has a bylaw that requires landlords to provide heating up to at least 21° C between September 15 and June 1 of each year (Municipal Code Chapter 497 Article 1).
  • Conduct regular maintenance, including ensuring your heating system is working properly.
  • Prepare for the possibility of power outages.
  • If you have a car, make sure it has a survival kit including a first aid kit and water.

Groups and organizations should develop a plan for how they will handle cold weather to ensure that everyone will stay safe.

 What to include in your plan:

  • Checking the weather forecast.
  • Rescheduling or limiting outdoor activities during Extreme Cold Weather Alerts or other wintry conditions.
  • Ensuring availability of warm drinks.
  • Ensuring children are dressed warmly, covering exposed skin.
  • Scheduling warm-up breaks for outdoor workers.
  • Training for staff to recognize and treat symptoms of frostbite and hypothermia.

Groups and organizations should also develop an emergency plan in case of power outage during the winter.