A total fire ban has been declared across Victoria's Mallee, Wimmera, North Central, and Northern Country districts.
The mercury is forecast to hit 37 degrees in Melbourne and 40 in some places, with strong northerly winds forecast for much of the state.
Fire Services Commissioner, Craig Lapsley, says residents in affected areas should prepare themselves for what he calls a serious fire day.
Meanwhile, the state's firefighting capacity has been boosted with the return of the Skycrane helicopter Elvis, on lease from the United States.
