Persistent heavy rain is forecast for parts of the north tropical coast in Queensland, potentially causing life-threatening flash floods and property damage.

The Bureau of Meteorology says a tropical low southeast of Cairns is dragging moisture into the region and the risk of heavy rain will increase over the weekend.

The area between Innisfail and Ayr could be worst affected, but the bureau says there is uncertainty over where the heaviest rain will fall. Townsville received 94.6mm since 9am today, causing flooding.

Six-hour totals of 100-180mm are likely, with isolated six-hour totals up to 220mm, while 24-hour totals of 200-300mm are expected, with isolated falls of up to 500mm.

“We are likely to see dangerous, life-threatening flash flooding occurring from this evening into the weekend where those highest rainfall totals occur,” meteorologist Miriam Bradbury said.

Riverine flooding is increasingly likely over the next couple of days, with impacts extending into next week. Initial and minor warnings have already been issued.

“Over the weekend as those incredible amounts of rain move through our water catchments, we are likely to see many of these flood watch areas and warnings upgraded to moderate to major flooding across a broad stretch of this coast,” Ms Bradbury said.

By late Monday, some isolated locations could receive more than 500mm or 600mm of rain, while the bureau says the region could experience marine gales and locally damaging wind gusts and surf.

Tropical low 13U near Cairns is one of six lows the bureau is monitoring across a region extending from southwest of Christmas Island to the eastern Coral Sea.

A tropical cyclone is expected to form southwest of Christmas Island early next week but is forecast to remain over open water and not directly affect coastal or island communities.

A low forming northwest of the Kimberly region in WA has a moderate risk of becoming a cyclone from Monday and is also expected to remain offshore.

A cyclone that could develop in the far eastern Coral Sea early next week is unlikely to directly affect the Australian mainland.

“There is uncertainty with the potential development of this tropical low, particularly with the possible development of other tropical lows along a trough that extends east across Vanuatu,” the bureau said.

“If the system develops, it is likely to track generally southwards through the eastern parts of the Coral Sea next week.”