Strong winds have caused chaos at Sydney airport with almost 100 flights in and out of the city cancelled, leaving thousands of travellers stranded.
The Bureau of Meteorology on Friday issued a severe weather warning for damaging winds over the state's southeast - stretching from the Victorian border up to the Hunter region.
Sydney Airport has been restricted to using only one runway, impacting international and domestic flights.
At least 50 domestic flights departing Sydney and 37 domestic arrivals into Sydney have been cancelled.
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Jetstar, Virgin, Qantas and TigerAir have all been effected.
A Virgin spokeswoman told AAP the situation is changing rapidly with very limited flights able to operate.
Bureau meteorologist Rose Barr said Sydney Airport had been hit with "fairly significant" winds, with gusts reaching up to 70km/h.
The strong winds are wreaking havoc near Newcastle airport at Salt Ash where a fast-moving bushfire has burnt through more than 1500 hectares of land.
Meanwhile in the NSW Alpine region the bureau has forecast winds averaging 80km/h with peak gusts of more than 110km/h and possible blizzards.
"This system has been throwing some wild and, in parts, quite hazardous weather at NSW and the ACT, to put it in context we have had fire and snow within 500 kilometres of each other," bureau weather services manager Jane Golding said in a statement.
Winds are expected to ease by Friday evening but will stick around for the weekend, Ms Golding said.
Qantas has scheduled additional flights on Saturday from Sydney to Melbourne and Brisbane to help recover from Friday's delays.
The winds are part of a massive weather system that threw a blanket of dust over Sydney on Thursday but blew out to sea on Friday morning.
Meanwhile, damaging winds with gusts of up to 120km/h are expected east of Orbost, in Victoria, on Friday.
The State Emergency Service has urged locals to move cars away from trees, secure loose items and keep clear of fallen power lines.
Further south, Tasmanian police are dealing with several calls about fallen trees in north-eastern parts of the state, with drivers urged to take extra care on the roads.
