Thousands of petrolheads have endured heatwave conditions to descend on the nation’s capital, as emergency services greenlit the iconic Summernats car festival despite a total fire ban.

Three people are missing in Australia as the southern regions grapple with spreading bushfires amid sweltering temperatures. A heatwave is feeding the flames as temperatures climb past 40°C. Authorities have described conditions as the worst since the Black Summer bushfires of 2019 and 2020,

Authorities are urging those in heatwave affected areas to use common sense, stay cool and look out for the elderly as temperatures soar past 43C.

More than 600 firefighters have been deployed and conditions are being closely monitored, but a southerly change forecast on Saturday afternoon is a concern among authorities.

The country was one of the hottest places on the planet on Wednesday as capital cities sweltered through extreme heat.

More than 30 people have presented to hospitals in NSW over the past 24 hours with heat-related illnesses as millions swelter through severe heatwave conditions exceeding 40C in some major cities.

Hello and welcome to Yahoo's live coverage of the extreme heatwave sweeping large parts of Australia this week. Victoria is bracing for a 'catastrophic day' with temperatures set to soar to 47C. Strong winds and thunderstorms will exacerbate the danger, with authorities fearing the conditions will quickly turn deadly if warnings are not heeded.