A heatwave is a period of unusually hot weather, that can last for several days. There is no set temperature for a heatwave – heatwaves are declared when the temperature becomes hotter than the usual temperature at your location.
Heatwave Forecast Service
The Bureau of Meteorology runs a Heatwave Forecast Service to show, in advance, areas of Australia that may experience above average temperatures for a period of three days or more. There are three levels of heatwave warnings: low intensity heatwave, severe heatwave, and extreme heatwave.
NSW Health Preparing Yourself and Your Home provides more information on preparing for a heatwave, including ways to reduce your risk of heatstroke, and medical conditions that might put you at increased risk.