Victoria's Christmas heatwave in the severe category

Neelima Coahan - Christmas
heatwave in Victoria.

Victoria's first summer heatwave will be severe, the weather bureau warns, with a cool change not expected until three days after Christmas.

The weather bureau released new maps on Wednesday showing the predicted Christmas heatwave is in the severe category for much of Victoria.

The mercury is set to soar on Friday, with Mildura set for a top of 38 degrees, Swan Hill 37, Echuca 36 and Bendigo 33.

The scorcher will continue on Christmas Day, with Melbourne set for a top of 35 degrees, Mildura and Swan Hill 41 degrees and Echuca 39 degrees.

In Bendigo, the peak will come on Tuesday with a maximum of 39 degrees.

"On Christmas Eve, the temperature is going to be low-30s," Bureau of Meteorology forecaster Tony Bannister said.

"But Christmas Day itself is going to see a further increase, so it's going to be pretty hot for your Christmas lunch It's probably a better idea to have it inside than outside."

On Boxing Day, the mercury is set to top 31 degrees in Melbourne.

Read Neelima Coahan’s story in the Melbourne Age - “Victoria's Christmas heatwave in the severe category.”