Cyclone Mitchell intensifies as towns in north-west WA brace for winds, flooding | Australia weather

The tropical cyclone in the north of Western Australia is expected to intensify and turn into category three.

Cyclone Mitchell was off Hedland Harbor and was moving south-west towards the coast off Karratha late on Saturday morning.

Authorities expect the cyclone to continue moving southwest and cross the western Pilbara coast on Sunday afternoon.

It was expected to intensify into a category three system as it passed just north of Karratha on Saturday night and follow a course close to the Pilbara coast on Sunday.

Very destructive winds could reach 170kph around Karratha, Dampier and Wickham, and Onslow further south, on Saturday night, according to the Bureau of Meteorology.

A watch and act warning was issued from Whim Creek to Mardie, including Barrow Island and Montebello Islands, and residents were told to prepare to seek shelter due to the potential threat to lives and homes.

Residents from Pardoo Roadhouse east of Whim Creek and south of Mardie to Carnarvon and Pannawonica were advised to monitor conditions and prepare for hazardous weather.

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An evacuation center opened at Karratha Leisureplex from midday on Saturday and people were advised to bring essential items such as medicine and ID but not pets.

The ports of Ashburton, Cape Preston West, Dampier, Port Hedland and Varanus Island were closed as the weather system approached.

Up to 130mm of rain was expected at Hedland Harbor on Saturday, bringing the risk of flash flooding.

The central and western Pilbara coasts are at risk of flash flooding over the weekend, with the western Gascoyne region likely to be affected on Monday, authorities have warned.

The bureau said abnormally high tides would pose a serious flood risk for the Karratha area into the early hours of Sunday and Onslow into Sunday afternoon.

The cyclone’s impending arrival comes at a time when other rural towns are still feeling the brunt of major flooding.

In the Northern Territory, more than 400 people who took the 230km bus from the Daly River to Darwin on Wednesday may have to wait days to return as river flooding is not expected to peak until early next week.

Incident controller Supt David Moore said 298 evacuees, including 110 children, were housed in Foskey Pavilion at Darwin Showgrounds.