Extreme heat events are characterized by prolonged periods of high heat in which evening nighttime temperatures remain high. Without adequate cooling mechanisms, prolonged exposure to this kind of heat can result in severe negative health consequences, including death. While everyone is susceptible to these effects, some demographics are more vulnerable than others. Some groups identified as being notably high risk include the elderly, infants and young children, pregnant women, the homeless, and those struggling with addiction and mental illness. Greater Sudbury, situated relatively far North for a major Canadian city, is less likely to experience extreme heat events than, say, Toronto is. However, such events do occur here, with the most recent one happening in the Summer of 2020. Climate change is only going to exacerbate the problem, with some reports indicating that the previous 50-year heatwaves may occur as frequently as every other year. Official documents produced by the City of Greater Sudbury indicate that they plan for a rise in average Summer temperatures of between 2.5°C and 3.5°C by 2050. This same report indicates that they expect more severe occurrences of extreme heat events, as well as increases in the rates of infectious disease and air quality/smog events. These concerns have since been incorporated into the updated versions of the Hot Weather Response Plan, the last version of which was released in 2016.
Recognizing that it had no specific plans for dealing with a major extreme heat event, in 2007 the City of Greater Sudbury, Ontario implemented their Hot Weather Response Plan in order to better protect their citizens from the dangers of extreme heat. The original document, being produced in 2004, did not make specific reference to climate change; that has now been corrected and the newest version of the plan, published in 2016, makes explicit reference to climate change and the dangers it poses with regard to extreme heat events. While the Hot Weather Response Plan incorporates protections for all citizens of the Greater Sudbury Area, the plan takes more precise and detailed cautions with regard to the highest-risk segments of the population. While the Hot Weather Response Plan had not yet been activated at the time this case study was written, it has since been activated during the Summer of 2020 in a period of intense and prolonged heat in early July of that year.