Poor air quality in Sydney after dust haze

The conditions prompted authorities in NSW and the ACT to issue health warnings, with asthma sufferers urged to remain indoors with the doors closed.

These people should limit their time outside until the dust storm passes and use air conditioners to keep the inside air clean.

In the interior of New South Wales locals reported great billowing columns of red dust blowing into towns and reducing visibility to a few yards in places.

NSW director of environmental health Dr Richard Broome said: "I think it's important for the rest of the day people are cautious".

"The strong winds associated with this dry soil, with a lack of vegetation are the flawless conditions to pick up the dust, lift it up into the atmosphere and bring it east with winds", Ms Pyne said.

However, it has already drawn comparisons to an intense dust storm which blanketed the city in 2009.

"It was incredible, everything turned red and it just blew the town away", she said.

"Dust may aggravate existing heart and lung conditions and cause symptoms like eye irritation and cough".

A pedestrian walks under the Sydney Harbour bridge as a dust storm blankets the city
Image The worst dust storm in recent memory was in September 2009

Although the woman had planned to take photos once every hour, the storm was moving so fast she changed her plan as the sky was quickly darkened with dust.

Parts of the state have already experienced dust storms this week with Griffith in southwest NSW covered by dust on Tuesday.

Narramore said the system may not be as large as the previous storm but could still pose health risks.

10 News First weather presenter Josh Holt said dust storms occur after a combination of sustained wind and dry weather.

Some flights at the city's main airport were delayed.

Sydney could face a repeat of the famous dust storm in 2009, which left the skies above the city a deep orange.

The dust set off smoke alarms and caused flights to be re-routed to Brisbane and Melbourne.

It comes just two weeks after drought-hit western NSW farmers had to contend with a horrendous dust storm rolling across the region.

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