Victoria and New South Wales face scorching heat that could break all-time temperature records in the coming days. Starting Saturday, a dome of intense heat will sweep across South Australia, Victoria, NSW, and southern Queensland. Inland areas may see over five days of temperatures above 40C. "The heat would be challenging for everyone," said senior meteorologist Jonathan How. He urged people to stay cool and watch fire and heat warnings closely. Fire danger will range from high to extreme, with catastrophic risk expected on the Yorke Peninsula in South Australia on Saturday. Fires are still burning in Victoria after an extreme heatwave earlier this month, linked to global heating. Winds are expected to be less gusty during this heat wave. Temperatures could soar into the high 40s Celsius. Oodnadatta, South Australia, already reached 34.7C by Friday morning. Adelaide is forecast to hit 42C on Saturday, coinciding with a tough stage in the Tour Down Under cycling race. In Victoria's Mallee region, temperatures could approach 49C by Tuesday, potentially breaking the state's record of 48.8C set in 2009. Mildura's temps will rise from 43C Saturday to 48C Tuesday. Melbourne will reach 40C Saturday and peak again at 42C Tuesday during the Australian Open. NSW will see heat spikes Sunday and midweek, especially in Riverina, central west, and northern areas. Bourke could near 49C on Wednesday, close to NSW's record of 50.1C from 1939. Thargomindah in southwestern Queensland may hit 48C Wednesday and Thursday. Western Australia faces ongoing heat and fire alerts as tropical low Luana nears its Kimberley coast, expected to become a category two cyclone. Australia had its fourth-warmest year on record in 2025, with temperatures 1.23C above average, raising the threat of more extreme weather like this heatwave. Hot days and nights are likely through April, with warmer sea temperatures around Australia continuing.