Extreme weather conditions in Victoria have resulted in the state's first code red catastrophic fire warning.
The ABC reports that the warning covers the Wimmera region in the state's west, where the temperature is forecast to reach 42 degrees Celsius on Sunday and 43C on Monday.
There is also a total fire ban for the entire state on Monday.
Rangers are closing parks and forests, and campers are being urged to leave as soon as possible.
The Country Fire Authority's chief officer Russell Rees says people must act now.
"We are concerned about their lives, the lives of their loved ones, their own lives and we want people to take action," he said.
"We want everyone to understand that you do not wait around for a fire and then get on the road. Being on the road during a fire is the most dangerous place to be."
Temperatures high in South Australia
Temperatures are high again across South Australia. Firefighters are on high alert, especially in the West Coast district.
Adelaide reached a top of 42C on Sunday and is expected to do the same on Monday - nearly 13C above average.
The ABC reports it will be Adelaide's fourth day of temperatures above 35C.
It is predicted that Renmark will reach 45C.
Ten of the state's 15 fire ban districts has been issued with a catastrophic warning on Monday.