Large yellow structures have popped up at intersections across south-east Queensland — but what are they?

Transport and Main Roads Queensland has revealed they are the state’s “innovative flood tuff units”, which aim to protect critical road infrastructure.

“These flood tuff units are designed to shield our electrical cabinets — which manage traffic signals, road lighting, and speed control — from flood waters up to five metres deep,” the department said.

“By safeguarding these systems, we’re working to keep communities connected and traffic operations continuing during and after severe weather events.

“These units are a key part of our cyclone response and recovery efforts to support local communities. We kindly ask that they remain in place for the safety of all road users.”

Authorities and residents are hunkering down and making their final preparations ahead of Alfred’s forecasted landfall tomorrow. 

Alfred is currently out at sea, about 145km east southeast of Brisbane and 110km east north-east of Gold Coast, and is moving at seven km/h towards the south-east coast.

The category 2 storm will likely cross over the Moreton Bay Islands tomorrow morning before crossing the mainland coast, most likely between Noosa and Beenleigh later in the day.

The system is bringing wind gusts up to 140 km/h and causing heavy rainfall and abnormally high tides, which are feared to trigger flash flooding.

It’s forecast to affect Double Island Point in Queensland to Grafton in New South Wales, with evacuation orders in place across the warning area.

This morning, more than 33,000 properties were without power across south-east Queensland and 35,000 in northern New South Wales.