Up to 10 millimetres of rain is expected on Saturday. Credit:Paul Jeffers

If you are heading to the AFLW grand final between the Western Bulldogs and the Brisbane Lions game on Saturday then expect to get a drenching, with the weather bureau predicting heavy rains.

But motorsport lovers can breathe a sigh of relief: the Formula One Grand Prix on Sunday will be largely spared, copping just a few light showers.

Bureau of Meteorology senior forecaster Michael Efron said the AFLW's big dance, which starts at 12.35pm on Saturday at Ikon Park, Carlton, could be "quite wet".

"It will rain for much of the game," Mr Efron said.