Families may need a wet weather school holidays plan over the coming days with forecasters warning large parts of Queensland are in for a drenching.
Bureau of Meteorologist forecaster Shane Kennedy said falls of 20 to 40 millimetres were expected, in abnormal conditions for this time of year.
"We're expecting rainfall mainly to start to build in the north-west of the state, so around the Mt Isa region today, and in addition, some enhanced showers around and on tropical coasts for today and Friday," Mr Kennedy said.
Mr Kennedy said the cloud band was expected to thicken up overnight and bring unseasonable "fairly substantial rain" across much of the state on Friday and Saturday.
"Apart from the far south-west and the far north, everywhere else is quite likely to see some rainfall over the next couple of days with the focus on Friday mainly through north-western and Central Queensland."
The Bureau of Meteorology said there was a chance of isolated storms around the Port Douglas region but there was far greater risk of fairly sustained rainfall state wide.
The rain was expected to continue into Saturday with falls of up to 40 millimetres before a lull on Sunday, with lingering activity around the Cairns and Charters Towers coastal regions.
A second cloud band was expected to form on Monday, bringing wet conditions from Rockhampton down to the Gold Coast, as well as eastern Queensland, with falls between 20 to 40 millimetre.
Mr Kennedy said the severity of next week's falls will depend on where the trough lands.
"Certainly with the second cloud band and how it's forming up, they're expecting a trough to form in the Coral Sea and depending on how close it gets to land and whether we see any low pressure systems forming in the next day that'll really help the focus of that rainfall," he said.
What's causing the unseasonal weather?
Mr Kennedy said it was rare to see such heavy falls in winter.
"In most places for July their average rainfall is around at 10 to 20 millimetres for the east coast and less than 10 millimetres for much of central and western Queensland," he said.
"They're quite unusual in that regard to that average, but we do see these cloud events every now and then."
Mr Kennedy said warmer oceans were creating prime conditions for increased rainfall, thanks to the tail end of La Nina.
"We've returned to overall neutral conditions in the Pacific but we still have some lingering warmer than average temperatures in the north-eastern Pacific Ocean," he said.
La Nina has ended but Mr Kennedy said there was a good chance it could return in a few months.
"There's a 50 per cent chance of seeing La Nina developing in spring or summer, so only one of the models has it forming in September, the others keep it in neutral conditions until summer or into next year.
"But conversely, the Indian Ocean is looking very likely that it will move into its wetter phase, it's the La Nina equivalent which is the negative Indian Ocean Dipole, so every model we survey is having that developing by August."
