Flood-hit north Queensland could be at risk of tornadoes

Flood-hit north Queensland could be at risk of tornadoes, with the state's weather disaster expected to continue until the middle of next week.

Townsville is now officially in uncharted territory after 1,012mm of rain fell on the city in the past seven days, smashing the previous record of 886mm in 1998.

The heaviest of the overnight rain fell north of Townsville, including at Ingham, which copped half a metre of rain in less than 24 hours.

Roads have been cut off and schools closed in the Queensland city. Source: 1 NEWS

But heavy falls are expected to return to Townsville today and well into next week, leaving thousands of evacuated residents there on edge and wondering when they might be able to go home.

The Bureau of Meteorology has extended the severe weather warning for Queensland's northeast coast, with the monsoon trough causing the destruction expected to track slowly south.

The flood risk now extends from Ingham, north of Townsville, as far south as Mackay.

Premier Annastacia Palaszczuk has again ordered schools that were closed in north Queensland on Friday to remain closed on Monday.

"We are in unprecedented times. There is more rain to come," she told reporters today.

Water levels have stabilised in Townsville, but that could change with very heavy falls expected to continue until the middle of the week.

Thousands of residents there have already fled their homes, and they've been warned it could take days for water that's swamped roads, yards, homes and businesses to recede.

Bruce Gunn from Bureau of Meteorology said the monsoon trough could generate tornadoes, with current severe weather warnings saying gusts of up to 125km/h are possible.

"There is some chance of tornadoes forming," Mr Gunn told reporters today.

"We've used the cyclone siren a few times already in this event. We have applied that in short bursts when there are events of heavy rain ...We will continue to do that for the most intense of hazards as they occur."

He said there'd been some reprieve for Townsville's Ross River Dam, with the heaviest of overnight falls north of its catchment.

Authorities have said the integrity of the dam is not in question.

It's currently sitting at 223 per cent of capacity.