Extreme Heat

Extreme heat can pose a health risk and even have lethal consequences. Click here for tips from the New Brunswick Office of the Chief Medical Officer of Health on how to identify and prevent heat-related illness and what to do in the event of heat stroke. 

Heat Alert and Response System

The City of Fredericton is a partner in the Province of New Brunswick Heat Alert and Response System (HARS). 

The effects of climate change pose risks to the health of Canadians and New Brunswickers, especially older adults, young children, and the homeless, as well as those with chronic health conditions and those using certain medications.

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For more about Heat Alerts, and what you can do to protect yourself, visit the ​Province of New Brunswick Heat Alert and Response System web page.

Effects of Extreme Heat

Extreme heat can occur throughout the summer months and can cause heat-related illnesses, exacerbate previous medical conditions, and potentially result in death. Extreme heat can lead to heat cramps, heat exhaustion, and heat stroke. Sustained exposure to extreme heat can pose a serious risk to many individuals. If the temperature inside a home is above 31°C for a sustained period of time, then there is significant increase in the potential risk for heat-related illnesses in susceptible groups.

The body has to work hard to cool itself down when exposed to extreme heat. It works to cool itself through the evaporation of the sweat, but in extreme heat, the body’s natural cooling mechanism may require additional support. Hydration and cool environments can help the body to cool itself down and avoid heat-related illnesses.

Heat alerts are shared through the Heat Alert and Response System to help warn people about the onset of extreme heat events.

Who is at risk?

Everyone is at risk of heat-related health complications, but there are some groups who are at increased risk. Those who have the potential to be the most affected are people over 60, people living with certain chronic disease, people experiencing homelessness or inadequate housing, and people who work outdoors.


Seniors are at increased risk for heat-related illnesses, but certain additional factors may increase their risk further. Seniors are more likely to have chronic health conditions (i.e., diabetes, cancer, heart or respiratory disease), to be taking medications, and to have mobility issues; the presence of any of these factors could increase the risk. These risk factors can make cooling off during an extreme heat advisory very difficult.

Homeless or inadequately housed 

People experiencing homelessness or living in inadequate housing individuals are at an increased risk for heat-related illnesses for many reasons. It could be difficult for individuals to find shelter from the sun, to stay hydrated, to get to cooling centres, and to access air-conditioned spaces. If they cannot cool their bodies down, they are at risk of illness.


People who work outdoors are at an increased risk for heat-related illnesses on hot days. The prolonged exposure they experience could make it harder for their bodies to cool down. This risk is high if individuals work all day in the direct sunlight. There are actions they should take to protect themselves.

Others at risk (dropdown)

Other individuals can also be at increased risk.

How can I reduce the risk?

You can reduce the risk of heat-related illnesses and complications by taking actions to beat the heat this summer. There are multiple measures you can take to keep you, your home, and others cool and protected from the heat. Staying cool is extremely important and the best thing that you can do to protect yourself from the effects of heat.

Keeping yourself cool 

  • Keep hydrated 
  • Take a cool bath or shower
  • Place cool/damp towels on the body (i.e., neck, arm pits, groin)
  • Spend time in air-conditioned areas
  • Use a fan when the temperature is not too high (over 35°C)
  • Open your windows when the temperature outdoors is lower than the indoor temperature
  • Take a cool bath or shower
  • Visit a cooling centre (could create a jump to Cooling Centres section of this document if bolded text is clicked)
  • Get out of the sun
  • Put on clothing that is lightweight and loose

Keeping your home cool 

  • Turn on your air conditioner if you have one
  • Turn on fans when the internal temperature of the home is below 35°C
  • Cover windows which are exposed to sunlight to block the sun when possible
  • Close windows in the daytime when the outdoor temperature is hotter than the indoor temperature
  • Open the windows, blinds, and shutters if safe to allow cooler air in when the outside temperature is cooler than the indoor temperature (usually nighttime and morning)
  • Make sure that all unused electric appliances and lights are off
  • Additional Resource: Indoor vs. Outdoor Peak Heat

Keeping others cool 

  • Make sure to check in on your family, friends, and neighbours who may be vulnerable to extreme heat to make sure they are staying cool. Use the health check guide for assistance with conducting an effective assessment to help keep others safe.
  • Encourage others to keep cool. If they are unable to keep their home cool, suggest they go to an air-conditioned public building, a cooling centre or that they come stay with you if your home is cool.
  • Additional Resource: Gov NB Community care workers and volunteers during extreme heat – Heat-related illnesses: prevention and preliminary care

    Key Messages

  • Remember to check on your family, friends, and neighbours during extreme heat warnings. Health checks can be conducted by anyone and they can be very effective at keeping others safe.
  • Certain groups of individuals are at increased risk for heat-related complications; these groups consist of seniors and homeless or inadequately housed individuals.
  • During extreme heat warnings, indoor temperature should be checked multiple times a day. Sustained exposure to heat at certain temperatures can be dangerous; monitoring indoor temperatures can help determine when a home is too hot and when it is time to cool down or leave.

Other Quick Messages

  • Cars can become extremely hot when turned off and parked. Make sure to NEVER leave anyone (animals or humans) inside of hot/warm cars. At hot temperatures, cars can cause death.
  • Take breaks from the heat whenever possible during extreme heat events. Remember, air-conditioned environments are best.
  • Remember to stay hydrated on days when the weather is extremely hot.


Remember to stay hydrated during an extreme heat event. Drink plenty of water and remember to drink it before you feel thirsty. If you wait until you’re thirsty, then you are already dehydrated. Dehydration leads to a decreased ability of the body to cool down through sweat evaporation which is the body’s main form of heat extraction. Water is the best liquid to drink to fight dehydration. Avoid caffeinated beverages and alcohol if possible as they are dehydrating beverages.

Cooling Centres

Cooling centres are essential tools during extreme heat events. They can provide relief during some of the hottest periods of the season. Visiting cooling centres more often and for shorter periods of time during a day may be more effective in bodily cooling. Cooling centres can be used by anyone, and they are especially helpful to those who are at increased risk for heat-related illness if they are unable to access other cool areas. Cooling centres are important for people without air-conditioned homes or for individuals who are homeless or inadequately housed.

Residents can seek shelter from extreme heat at the following locations:

  • a community cooling center operates in the basement of St. Paul's United Church Monday to Friday from 1 to 4pm until August 31, 2022. 
  • City owned facilities - Grant Harvey Centre and Willie O'Ree Place
  • the Fredericton Public Library, local malls, pools, lakes and splash pads 

Indoor vs. Outdoor Peak Heat

During extreme heat events, there is usually a time of day that is hottest. This can be referred to as the peak heat temperature of the day. The peak heat time of day differs depending on whether someone is indoors or outdoors. The peak indoor temperature is experienced later in the day compared to the peak outdoor temperature.

The peak outdoor temperature usually happens throughout the later hours of the afternoon.

The peak indoor temperature usually happens at evening times.

The heat has a bit of a delayed effect on indoor temperature, but it can still make the temperature significantly higher than normal.

Additional Resource: Indoor and Outdoor Peak Heat

New Brunswick based resources

ActionstoBeattheHeat.pdf (gnb.ca)/GestesPoserpourProtegerChaleur.pdf (gnb.ca)

Medicationsandtheheat.pdf (gnb.ca)/Medicamentsetchaleur.pdf (gnb.ca)

WorkersVolunteersDuringHeat.pdf (gnb.ca)/ CommunautairesBenevolesExtremeChaleur.pdf (gnb.ca)