Article published on the 2009-09-23 Latest update 2009-09-23 12:56 TU
Gale-force winds dumped thousands of tonnes of red desert dust on Australia's biggest city, shrouding it in an eerie orange haze and coating the Sydney Opera House in a fine layer of powder.
In the worst storm since the 1940s, dust covered most of New South Wales, Australia's most populous state, pushing air pollution to record levels and depositing about 75,000 tonnes of powder in the Tasman Sea every hour.
"Dust storms like this occur quite regularly but they rarely travel this far east and come through Sydney," said John Leys, principal research scientist with New South Wales' Department of Climate Change and Water.
Traffic was at a standstill, flights were cancelled and ferry service was interrupted in the state capital as people took to wearing facemasks before braving the streets.
Australia, in the grip of a decade-long drought, is emerging from an abnormally hot southern hemisphere winter including the hottest August on record.
Elsewhere in New South Wales, hail stones "the size of cricket balls" smashed windows as thunderstorms and gale-force winds lashed the state late on Tuesday.
Victoria state was on alert for flash floods as heavy rains fell, following a pair of minor earthquakes on Tuesday. The 3.0- and 2.6-magnitude tremors did not cause any damage, officials said.