Santa will need speedos as heatwave hits

The traditional Christmas Day roast may be hot but Victoria's weather will be sizzling over the holiday period with the state expected to experience its first heatwave of the summer.

A five-day hot spell is due to begin on Friday with the mercury tipped to hit 29C in the city.

It will be followed by four days above 30C, with Saturday likely to hit 32C, Christmas Day reaching 35C, Boxing Day at 31C, and a sultry 36C possible on Tuesday.

In the north of the state, the temperature on Christmas Day is forecast to soar into the low 40s where it will continue to hover on Boxing Day.

Bureau of Meteorology senior meteorologist Tony Bannister says Victorian temperatures will remain warm overnight during the Christmas holiday period with no real relief, especially inland..

"Please take care during this period over Christmas, and remember to try and stay cool," he said.

Mr Bannister said it was possible a cool change could arrive on Wednesday.

A low may come in from Australia's northwest bringing much-needed relief after the Christmas roasting.