Evacuations, closures and sandbags as cyclone closes in

Large sections of the Whitsundays coastline were told to evacuate early on Sunday afternoon, due to a large tidal surge forecast for the area.

Weatherzone meteorologist James Casey said the tidal surge was a combination of several different weather elements creating "a perfect storm".

Mr Casey said the Whitsundays was expecting a swell of up to four metres, which would be whipped up even further by the strong winds of more than 250 kilometres an hour expected as a result of the cyclone.

He added the heavy rain forecast for the area would also see the height of estuaries, rivers and lagoons rise, but the water wouldn't be able to drain away out to sea due to the large tidal surge pushing it all back inland.

Mr Casey said all of the factors generated a "knock-on effect" and were expected to cause flash flooding in the area once the wild weather arrived.

Tropical Cyclone Debbie was located an estimated 475 kilometres east-northeast of Townsville just before 2pm on Sunday and classified as a category two system.

However, the Bureau of Meteorology expected it to be a category four or five when it crossed land between Townsville and Proserpine early on Tuesday morning.

The weather bureau said it was the most significant cyclone since Tropical Cyclone Yasi in 2011 in terms of both "size and extent".

The severe weather system was expected to generate wind gusts up to 260 kilometres an hour as well as heavy rain as far inland as Charters Towers, more than 100 kilometres west of Townsville.

Premier Annastacia Palaszczuk announced schools between Ayr and Proserpine would be closed on Monday, with further closures likely due to conditions associated with the cyclone.

Ms Palaszczuk said charter boats along the coast had been secured, ports closed and people on islands had been told to seek shelter. Those on remote islands with no adequate shelter to withstand the cyclone have been urged to evacuate.

Emergency services said preparation was essential and warned residents to do it on Sunday because Monday may be too late. This included cleaning up and securing items around the home as well as organising an emergency plan.

They also advised locals not to travel on the roads once the wild weather started, to minimise risk to both themselves and emergency service crews.

Queensland Fire and Emergency Services commissioner Katarina Carroll said "substantial emergency services" had been deployed across the region and was confident they were ready to respond immediately, but warned locals not to be complacent.

An extra 1000 emergency services personnel were sent to the affected area, while more than 800 power workers were also ready to go in north Queensland and a further 200 were on the way.

Meanwhile, more than 250 kilometres north in Townsville, residents were frantically filling sandbags to guard against flash flooding.

One car park in the city's south was like an ant hill as cars came and went all day Sunday - as locals stocked up on tonnes of sand.

The council was preparing for 20,000 sandbags to be snapped up across the city in preparation for Tropical Cyclone Debbie's arrival.

Full hessian sacks and even plastic supermarket bags loaded down cars of all types as residents who had often seen this drill several times before left to shore up homes.

Other supplies were going fast, with supermarket shelves emptied and fuel being bought by the jerry can.

Townsville mum and BP worker Stacey Trainer said people had been "going crazy" filling up with fuel.

"We had people fighting over pumps," she told AAP.

"There were people filling up like 10 jerry cans."

Airlie Beach locals were "scared stiff" at the thought of the approaching cyclone, but backpackers didn't share the same level of concern.

Gemma and Matt Dungey, who work at the local BIG4 caravan park, said they had been through a category two cyclone before, but were worried ahead of the category four Tropical Cyclone Debbie.

"We had to warn all the guests about it, I did get home feeling a bit anxious," Ms Dungey said.

In contrast, a staff member at a backpackers hostel, who declined to be named, said about 15 tourists planned to head north despite the weather warnings.

"The backpackers don't believe it," she said.

"I just told them to take water, money, food.

"We want everyone to stay safe."

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