Forecasters expect minor flooding in the Brisbane and Bremer rivers, and parts of Brisbane are expected to flood, the premier says.
If current projections play out, 3600 residential properties will be affected in Brisbane, Lord Mayor Graham Quirk said.
He said of those 2100 were unit dwellings, where the ground floor might be flood but upper levels would not.
'There would also be 1500 detached homes that would be impacted if that scenario were to occur,' Mr Quirk said.
He said 1250 business properties would also be affected in Brisbane.
'This is not 2011. It is a much lesser event,' Mr Quirk said.
Mr Newman said there would be minor floods in the Brisbane River, and in the Bremer River that flows through the city of Ipswich to the west of Brisbane.
He said flood maps would shortly be released by the Brisbane and Ipswich councils, with lists of affected suburbs.
'The peak of any flood will occur in Ipswich we believe around midnight tomorrow (Monday) night,' Mr Newman said.
'Similarly the peak at the western side of the Brisbane City Council boundary will be about midnight on Monday night.'
He said the worst of the projected flooding would be seen in the heart of Brisbane around noon on Tuesday, with another peak expected at noon on Wednesday.
'The flood levels projected will be much lower that what we saw in 2011,' the premier told reporters on Sunday afternoon.
Mr Newman said flood peaks would be much less than what was experienced in 2011.
Brisbane is expecting a 2.6m flood peak, nearly half of the 4.46m peak in 2011.
The Ipswich peak is expected to be five metres less than the 19.4m in 2011.
'There will be flooding but the flooding is much much lower than what we saw in 2011,' he said.
Mr Newman said the projections were based on the best scientific modelling by forecasters.
He said the projections may not eventuate, but authorities had a duty to share the information so residents of both cities could be as prepared as possible.