Staff at a remote weather station are poised to evacuate as a cyclone bears down on them on its way to threatening Queensland.

Tropical Cyclone Jasper intensified into a category four system on Friday and is on track to hit the north Queensland coast between Cooktown and Townsville by mid-next week.

But the large system’s current course has already sparked contingency plans for the Bureau of Meteorology’s Willis Island station, which is about 450 kilometres off Cairns in the Coral Sea.

Tweet from @BOM_Qld

Four staff members are about to be evacuated, with the station in Cyclone Jasper’s reach and path.

“In terms of our Willis Island crew, we are putting in firm plans to look at what we do with them over the coming days, with decisions to be made on them over the course of today,” the bureau’s Dave Grant said on Friday.

A bureau spokesperson said the remote station was built to withstand a category five cyclone but staff safety was the priority.

Jasper is forecast to weaken over the weekend but is expected to intensify again into a severe tropical cyclone as it approaches the north Queensland coast next week.

A cyclone watch – a warning issued when impact is expected within 24 and 48 hours – could happen as early as Sunday.

“There is still a considerable amount of uncertainty [about] how strong and where the system will track over the coming days,” Grant said.

State Emergency Services Minister Mark Ryan urged Queenslanders to be prepared and mindful of warnings as the unusual cyclone approached.

The system is the first tropical cyclone to form in Queensland waters in December in an El Nino year.

“It’s unusually early for Queenslanders,” Ryan said of Cyclone Jasper’s arrival.

“Cyclones can obviously have devastating impacts on community, property and life.

“This is not a practice. This is not a drill. This is the real deal … continue to pay attention to authorities.”

Jasper was about 1200 kilometres east-north-east of Cairns at 9am (AEST) on Friday and moving south across the Coral Sea at 10km/h.

Heavy rainfall is expected along the central and north Queensland coast from Monday with flood watch alerts possible.

Severe heatwave conditions in Queensland’s far north and south-west are forecast to ease as the cyclone approaches.

“Tropical Cyclone Jasper is quite a large system,” the bureau’s Laura Boekel said.

“Which means that it does have quite a lot of cloud bands associated with that, bringing showers, rain and thunderstorms.”

Jasper is expected to bring heavy showers across Queensland, beyond its immediate impact area.

“We could definitely see rainfall ranging quite far out from where that core of that cyclone is,” Boekel said.

“Quite large areas could see severe storms as well as rainfall that could produce flash or riverine flooding.”

The state disaster centre has been moved to alert level, Queensland Police’s Acting Deputy Commissioner Shane Chelepy said.

Preparations have also been made with local and district disaster coordinators from Mackay to Cairns.

Cairns is preparing for king tides of up to almost three metres from Tuesday to Sunday next week, which may be exacerbated by the cyclone and prompt storm surge evacuations.

– AAP