Six low-lying Townsville suburbs have been evacuated as emergency services brace for flood waters predicted to reach second-storey levels.

Thousands of people have been displaced, and one life lost after an SES boat evacuating a woman from Ingham hit a submerged tree and capsized into floodwaters.

Some areas have copped half of Townsville’s annual rainfall in 24 hours in the deluge stretching from Cairns to Mackay, with residents living in the ‘black zone’ warned the Ross River is rising fast.

Floods have driven crocodiles from rivers to roadsides, and multiple rescue crews have been deployed to evacuate residents requiring help.

The remaining residents have been told to seek high ground, and warnings have been issued that stretches of the Herbert River could reach a 60-year high.