Girl, 9, drowns after being swept away by floodwaters near Cooktown

A nine-year-old girl has drowned in floodwaters south of Cooktown in far north Queensland.

Police said she was swept off a crossing at Rossville while swimming with family and friends about 2:30pm on Saturday.

A local swiftwater rescue team found the girl's body a short time later, about 400 metres downstream.

Police are investigating the circumstances.

Areas of the north tropical coast between Cape Tribulation and Cardwell were put on flood watch this weekend, after a monsoon trough was predicted to dump up to 300 millimetres of rain between Saturday and Monday.

In the Bureau of Meteorology's (BoM) latest flood watch issued on Sunday, they said the highest rainfall totals are expected north of Cairns, where totals of 200-300 mm are possible from Sunday through to Tuesday.

South of Cairns, rainfall totals up to 100 mm are forecast.

Catchments at risk within the flood watch area include the Daintree, Mossman, Barron, Mulgrave, Russell, Johnstone, Tully and Murray rivers.

BoM forecaster Rick Threlfall said a cyclone was likely to form in far north Queensland by mid next week but they were unsure exactly where it will form.

Mr Threlfall said the rain is expected to continue for several days and the BoM is monitoring several small low pressure systems that have formed off the monsoon trough.

"Exactly which one will develop into a cyclone is still pretty uncertain at this stage," Mr Threlfall said.

"It looked like it was going to develop in the Gulf of Carpentaria but the situation is developing day by day and there is the chance of that switching to the Coral Sea."

Overnight, rainfall around the Cairns region was moderate.

According to the BoM, Cairns Racecourse received 31mm in the 24 hours to 9:00am on Sunday.

The Queensland Fire and Emergency Service (QFES) said specialist swiftwater rescue crews would be based in Cairns, Cooktown and the Douglas Shire for the coming week.