Victoria

Temperatures of over 40C, strong winds, thunderstorms and a change of wind direction meant Monday would be a day of extreme danger, officials said.

Emergencies chief Andrew Crisp said those in the East Gippsland area should leave no later than Monday morning.

More than 100 fires are continuing to burn across Australia.

The biggest are raging near the city of Sydney in New South Wales, where more than a quarter of a million people have signed a petition calling for the New Year's Eve fireworks to be cancelled and the money spent on fighting fires.

Heavy rain continued to fall across much of the Australian state and authorities prepared for possible evacuations in the north-east.

The state is enduring what the weather bureau says is an "unprecedented" deluge that could bring three months' of rain in three days, with another 150mm forecast to fall in some areas.

While the threat has eased somewhat in Melbourne, emergency workers are paying particular attention to the north-east ranges, where significant flooding is expected and warnings have been issued for the Ovens and King rivers.

The storm continues to batter southern New South Wales, Victoria and Tasmania.

A body was found in the swollen Cotter River near Canberra on Monday morning.

Erosion at Sydney's Collaroy Beach has forced the evacuation of multi-million dollar homes, which are now in danger of collapsing.

Flood warnings have been issued across several states, with northern Tasmania facing its worst flooding in decades on Monday.