Massive rain band to bring more storms, flooding and windy weather to Australia’s east coast

A massive rain band moving across the country towards the east coast is threatening to bring severe thunderstorms, flash flooding and gusty winds in the coming days.

Inland Queensland and northern New South Wales were expected to be hardest hit by thunderstorms, with flooding also likely.

The rain band was expected to move into the western parts of Queensland, NSW and Victoria on Wednesday night, before moving through the rest of the eastern states on Thursday.

Between 15 and 40mm of widespread rainfall was forecast, some of it in areas that are already wet, according to the Bureau of Meteorology senior meteorologist Christie Johnson.

"This might not sound like a lot of rainfall but, given that a lot of it is going to be falling over currently saturated and already flooded areas, we are expecting to see renewed river rises and potential prolonging of existing flooding," she said.

"We have many flood warnings out at the moment, particularly through inland NSW, parts of southern Queensland and Victoria, and we will be issuing further flood watches and warnings as required," she added.

The BoM has issued a minor flood warning for the Macquarie River, and minor to moderate flood warnings for the Bogan, Lachlan, Murrumbidgee, Murray and Edward rivers.

It said the system may also bring large wind gusts and hail, particularly over elevated areas.

The cold front had already hit South Australia and southern parts of the Northern Territory.

The system was forecast to intensify on Wednesday afternoon over eastern South Australia and the south-eastern Northern Territory as the front combined with tropical moisture from the Indian Ocean and the Coral Sea.

Johnson said Australia was in the midst of a negative Indian Ocean Dipole event, which was producing the higher rate of rainfall over the east coast.

"We also have above average sea surface temperatures around Australia. These conditions mean that there's a lot of available moisture that can be dragged into these weather systems as they cross the country," she said.

"The October to December outlook suggests wetter than average conditions for most of eastern Australia."

Johnson said there was a 70% chance of a La Niña event developing during the spring, which was contributing to the wetter than average outlook.