Heat Alerts & Heat-Related Illness

The City of Hamilton’s Heat Alert and Response System, also known as H.A.R.S., includes seasonal monitoring and three response stages.

From May to September, we monitor weather forecasts, including the humidex and smog, for conditions that can increase health risks.  The three response stages and their triggers are:

  • Stage 1 Heat Advisory - one day with a forecasted temperature of 31 C or more and humidex of 40 or more 
  • Stage 2 Heat Warning - either two or more consecutive days with a minimum forecasted temperature of 20 C or more and a maximum temperature of 31 C or more; or a humidex of 40 or more. 
  • Stage 3 Extreme Heat Warning -three or more days with an observed minimum temperature of 20 C and a maximum temperature of 31 C.

Prepare for the heat before it arrives:

  • If you take medication, speak with your doctor or pharmacist about how your medication affects your risk for heat-related illness.
  • If you have an air conditioner, make sure it works properly. If you have ceiling fans or other fans, they can help as long as the temperature is not too high.
  • Talk to family, neighbours and friends and make a plan for visits on hot days. Visitors can see signs of heat-related illness that could be missed over the phone. Make plans to visit air-conditioned places such as a mall, library or community centre during heat alerts. Even a few hours every day in air conditioning will help.
  • During warm weather, check local weather forecasts so you know when to take extra care.

During a Heat Advisory, stage 1 of the Heat Alert Response, the following places are open for residents to go to cool off.  Check what hours they are open before you go.

City of Hamilton sites

Community sites 

Extreme heat can cause heat cramps, heat exhaustion, heat stroke and death. Take precautions to reduce your risk of heat-related illnesses. See below for ways you can reduce your risk.

During a Heat Warning, stage 2 of a Heat Alert Response, the following places are open for residents to cool off. Check what hours they are open before you go.

City of Hamilton sites

Indoor and outdoor pools

Regularly scheduled public, family, adult and senior swims are free of charge at City of Hamilton indoor and outdoor pools.

There is free swimming on Saturday and Sunday from 6 to 8 pm at the following pools during a Heat Alert Stage 2 Response:

Pool capacity limits are in effect during a Heat Alert. We may use swim rotations, depending on line-ups at each pool (i.e., people can swim for one hour only, and the next group of people can swim for one hour).

Other City of Hamilton sites

Community sites 

Summer Supie programs

Summer Supie programs in Hamilton parks with water stay open during stage 2 of a Heat Alert Response. Supie program locations without water will close.

Free drinking water

The Salvation Army gives out bottled water between 10 am and 2 pm at Gore Park during a Heat Alert.

Extreme heat can cause heat cramps, heat exhaustion, heat stroke and death. Take precautions to reduce your risk of heat-related illnesses. See below for ways you can reduce your risk.

During an Extreme Heat Warning, stage 3 of a Heat Alert Response, the following places are open for residents to cool off.  Check what hours they are open before you go.

City of Hamilton sites

Indoor and outdoor pools

Regularly scheduled public, family, adult and senior swims are free of charge at City of Hamilton indoor and outdoor pools.

There is free swimming on Saturday and Sunday from 6 to 8 pm at the following pools during a Heat Alert Stage 2 Response:

Pool capacity limits are in effect during a Heat Alert.We may use swim rotations, depending on line-ups at each pool (i.e., people can swim for one hour only, and the next group of people can swim for one hour).

Other City of Hamilton sites

Community sites 

Summer Supie programs 

We close Summer Supie programs during stage 3 a Heat Alert Response.

Free drinking water

The Salvation Army gives out bottled water between 10 am and 2 pm at Gore Park during a Heat Alert.

Extreme heat can cause heat cramps, heat exhaustion, heat stroke and death. Take precautions to reduce your risk of heat-related illness such as:

  • Drinking lots of water
  • Going to an air-conditioned place such as your home, the mall, library or community centres.  See a list of City of Hamilton and community sites with air conditioning open to residents in the section Heat Alert Stage 1 Response above.
  • Wearing a hat and loose-fitting, lightweight clothes
  • Taking a bath or shower with cool water or if this is not possible, running cool water over your wrists or putting your arms or feet in cool water
  • Closing your blinds or curtains
  • Opening your windows to let air circulate while using a fan, only if the outdoor air is cooler than the indoor air
  • Limiting physical activity during the day
  • Having cold meals to eat
  • Cooking outside instead of turning on the stove
  • Calling your doctor if you have heavy sweating, paleness, muscle cramps, weakness, tiredness, dizziness, headache, fainting, nausea and/or vomiting

Never leave pets or children alone in closed vehicles, especially when it is hot outside.

Help others by checking on your neighbours and family to make sure they are OK.

Information about what to do to reduce your risk of heat-related illness is available in the following languages: