Two cyclones in Australia's north have caused storms and flooding, affecting mining and energy projects for companies including Rio Tinto Group and Woodside Petroleum Ltd.

Tropical Cyclone Dianne was 385 kilometers (240 miles) northwest of the Western Australian town of Exmouth and near stationary at about 11 p.m. local time, according to the Bureau of Meteorology. The storm is forecast to intensify from Category 2 to Category 3 by 11 p.m. tomorrow as it moves southwest. Flood warnings are in place for some Pilbara and Mid West regions.

The storm slowed transport at Rio Tinto's iron ore operations in the Pilbara and halted production at Woodside's Enfield oil field. A La Nina event has brought wet weather to Australia's east and north and typically increases the number of cyclones during the November to April period, according to the bureau.

Rio Tinto, the third-biggest mining company, said its transport infrastructure is "slowly getting back to normal, but not there yet." There's been no obvious impact to production, Perth-based spokesman Gervase Greene said in an e-mailed statement today. Access to roads is "still problematic" and the London-based company is checking for damage to its rail lines, he said.

Woodside, Fortescue

Woodside, Australia's second-largest oil and gas producer, said its Enfield oil field off northwestern Australia remains closed today. Production was halted yesterday, Perth-based spokeswoman Laura Hammer said in a phone interview.

Rain has created "management issues for staff" for Fortescue Metals Group Ltd., spokesman Cameron Morse said in a phone interview from Perth today. He declined to say whether production for Australia's third-biggest iron ore miner had been affected.

In the Northern Territory, Ex-Tropical Cyclone Carlos has been downgraded to a tropical low after hitting Darwin with gale-force winds and record rainfall. At 11 a.m. local time, Carlos was over land 115 kilometers southeast of Darwin, moving at 8 kilometers an hour. It's forecast to re-intensify into a Category 1 cyclone by Feb. 19 as it heads toward the Western Australian town of Kununurra.

Darwin has recorded more than 400 millimeters (16 inches) of rain since Carlos formed, triggering flash floods, blackouts and closing the city's airport and schools, ABC News reported today.

Queensland state, on Australia's east coast, was hit earlier this month by Tropical Cyclone Yasi, packing winds stronger than Hurricane Katrina, which devastated New Orleans. Yasi followed deadly flooding in January and record December rain.

To contact the reporters on this story: Jason Scott in Perth at jscott14@bloomberg.net;

To contact the editor responsible for this story: James Poole at jpoole4@bloomberg.net