Heatwave update: Where and when is the heat expected to hit and what records could fall?

Heatwave conditions will see much of the continent swelter this week, with records set to tumble. Key points: Adelaide is forecast to be 40C and hotter from Tuesday to its peak of 44C for Friday Canberra could blitz the previous record of 41.6C, with 43C forecast for Saturday Australia's hottest day on record, calculated by averaging temperatures from across the country, could fall later in the week Western Australia is just starting to get a little relief, but South Australia is next to feel the heat as a hot air mass moves slowly east — dragging the bushfire danger up with it. The big record in peril this week could be Australia's hottest day on record, calculated by averaging temperatures across the country. Categorising heatwaves Heatwave severity Low-intensity The level of heat expected is unusual, but injury to people is not generally expected unless inappropriate activities are conducted or sensible precautions are not undertaken Severe Vulnerable people are at risk of injury Extreme Likely to cause impact across multiple areas such as infrastructure, transport, energy, agriculture and both healthy and vulnerable people are at risk of injury Source: Bureau of Meteorology John Nairn, the BOM's national heatwave project director, describes heatwave severity levels using a cricket analogy: During a low-intensity heatwave, the whole family can be out playing and enjoying the sun, grandparents included, providing you take normal conditions like drinks and hats; When it becomes severe, it is not a good idea for the grandparents to be outside; When you get to an extreme heatwave, why are you even playing cricket? Fatalities in extreme weather: Hazard Period Fatalities High-risk states Extreme heat 1900-2011 4,555 Vic, NSW, SA Flood 1900-2015 1,859 Qld, NSW Tropical cyclone 1900-2015 1,216 WA, NT, Qld Bushfire 1900-2011 825 Vic, NSW, Qld Wind storm 1900-2015 525 NSW, Vic, Qld Source: Andrew Gissing, Risk Frontiers This week is likely to be record-breaking, but it is unlikely to be the end.