Heatwaves are generally acknowledged as a period of unusual and uncomfortable hot weather that could negatively affect human health.

The Bureau of Meteorology defines a heatwave as occurring when the maximum and the minimum temperatures are unusually hot over a three-day period at a location. This is considered in relation to the climate and past weather at a location.

Extreme heat can affect everyone; however, some people are more vulnerable. Extreme heat can also affect infrastructure such as electricity supply, transport (roads and rail) and other services resulting in power outages, delays or cancellations of rail services or failures of traffic management systems.

Examples of significant heatwaves in Victoria include:

  • 2009 - consecutive days of temperatures above 43°C in late January followed by a record 46.4°C on 7 February culminated in the Black Saturday bushfires
  • 2014 - hottest four-day period on record, from 14-17 January 2014.

Both heatwaves resulted in widespread impacts on the health system, public transport disruptions and power outages. The former Department of Health and Human Services released the January 2009 Heatwave in Victoria: an Assessment of Health Impacts report covering the health impacts of the heatwave incident in 2009. 

All links in the table below will open in a new window.
Publish year Assurance activity Summary Organisation
2024 ACOSS Summer Heat Survey 2024 (External link) Heatwaves are by far the greatest cause of extreme weather-related deaths. Climate change is exacerbating the intensity and duration of hot conditions – but many homes are not built to withstand them. This report makes 10 recommendations towards cooler, healthier and more climate-resilient homes, putting people with the least at the centre of government policy and planning. Independent
2023 ACOSS 2023 Heat Survey (External link) Exposure to heat is a threat to people’s health, with more people dying in Australia from heatwave than all other extreme weather events combined. The survey findings clearly show that high heat has negative impacts for people on low incomes, seriously affecting their mental and physical health, productivity and capacity to conduct essential activities. Independent
2023 Let’s talk about the weather: injuries related to extreme weather (External link) The past decade has seen increasing injuries related to extreme weather – such as heatwaves, bushfires and storms. With the exception of Tasmania, exposure to excessive natural heat was the most common cause leading to injury hospitalisation for all states and territories. The report suggests opportunities to develop weather-related injury surveillance systems.
Australian Government
2021 Feeling the Heat (External link) A report exploring the impact of extreme heat and outlines the risk factors that exacerbate heat vulnerability. It reflects current research, consultation with the Victorian community sector, a survey of community organisations about their experiences of heatwaves, and interviews with clients across the state. The report proposes recommendations to reduce the harm caused by extreme heat and strengthen the services provided to people experiencing disadvantage. Victorian Council of Social Service
2018 Heatwaves in Victoria: A Vulnerability Assessment (External link) A study of the extent of heatwave vulnerability in Victoria and how it spreads across sectors and geographical areas, it provides insight on the inter-linkages between sectors. Based on these criteria the agriculture, construction, health, environment, and electricity sectors are assessed as the highest priority sectors for heatwave adaptation policy effort. Department of Environment, Land, Water and Planning
2014 2014 Heatwave Management: Reducing the Risk to Public Health (External link) After the January 2014 heatwave, the Victorian Auditor-General's Office investigated whether applying the then Department of Health's heatwave framework was effective in reducing the impact of extreme heat on public health. The report includes a comparative analysis with the outcomes from the 2009 January heatwave, outlines VAGO's findings and associated recommendations Victorian Auditor-General's Office
2014 The health impacts of the January 2014 heatwave in Victoria (External link) Analysis of the health impacts of the January 2014 Victorian heatwave, with comparisons to the outcomes of the January 2009 heatwave. Department of Health
2012 January 2009 Heatwave in Victoria: an Assessment of Health Impacts (External link) A report analysing the health impacts of the January 2009 Victorian heatwave. Department of Health and Human Services
2011 Evaluation of the Victorian Heatwave Framework - Executive Summary (External link) An evaluation of the Victorian heatwave framework, the report summarises the discussion, outlines the recommendations and the Department of Health's responses. Department of Health
2010 Report on Department of Health's January 2009 heatwave in Victoria: An assessment of health impacts (External link) A parliamentary committee appointed to inquire into and report on Victorian departmental and agency performance and operations of the year 2009 resolved to invite the Department of Health to give evidence at a public hearing with respect to the Department’s January 2009 Heatwave in Victoria: an Assessment of Health Impacts report. This report provides an overview of the Committee's public hearing with the Department in relation to its report, together with follow-up matters. Parliament of Victoria