Victoria is set to face record-breaking heat with temperatures forecast to reach 49C in the Mallee town of Ouyen, breaking the state's previous high of 48.8C set in 2009. Melbourne is expected to hit 45C, its hottest since Black Saturday 2009. The fire danger rating is extreme amid six major fires across the state. Country Fire Authority chief Jason Heffernan urged people to avoid unnecessary travel, saying Tuesday is "not a day for complacency." Four zones near the Carlisle River fire in the Otways have been ordered to evacuate immediately due to serious threats to homes and lives. An extreme fire danger warning remains across much of South Australia with total fire bans in place for several districts. The heatwave is expected to last days, with Ouyen experiencing nine consecutive days over 40C. Senior meteorologist Jonathan How called temperatures above 48C "extremely rare." Victoria’s chief health officer Dr Caroline McElnay warned about heat-related illnesses, urging people to watch for symptoms like dizziness, nausea, and confusion, and to call emergency services if heatstroke signs appear. The heatwave extends to parts of South Australia and New South Wales, with more records possible. Experts link the severity of the event to the ongoing climate crisis, which increases extreme weather risks. Hot conditions are expected to continue until April, with unusually warm sea temperatures around Australia.