The weather bureau has made a BIG change to Thursday’s forecast!

Melbourne is set to swelter on Thursday, with the bureau revising its forecast to 39 degrees.

The city was initially predicted to reach of a top of 34.

If Melbourne cracks 39, it will be the hottest day since we hit 42 degrees on January 25, earlier this year.

Thankfully, a cool change is also forecast to arrive in the afternoon.

The forecast top for Friday is 20 degrees, with the weather expected to be slightly warmer across the weekend.

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