The SES has advised people to stay indoors and move cars under cover.
A man has died after being struck by a tree on the NSW Central Coast as wild weather continues to bring dangerous conditions across the state.
The 76-year-old man was hit by the falling tree at a home on Glenworth Valley Road on the Central Coast, and was unable to be revived by emergency workers who were called to the scene about 1:30pm.
The tragedy occurred as severe thunderstorms swept through Sydney and its surrounds, hitting Richmond, Camden, Campbelltown and Penrith in the early afternoon, as well as the Hunter, with warnings stretching as far as Tamworth, Bourke, Scone, Walgett and Coonabarabran.
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At about 1pm, emergency crews also responded to a large gumtree falling onto a house on Kurrajong Road at North St Marys, where a woman and her baby were inside.
There were no injuries, and they were taken to Nepean Hospital for mandatory testing.
"She was just very shaken up, she was just thankful that we were there to put her in the car," a witness told 9News.
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The SES has so far received more than 620 calls for help, more than 200 of which have come from Blacktown.
The Bureau of Meteorology has said the severe thunderstorms in Sydney have temporarily eased, but that they could redevelop later today.
The BoM has warned that severe thunderstorms were likely to produce damaging winds and large hailstones in the state's north, between Taree, Kempsey and Mungindi, over the next several hours.
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Light rail services between Carlingford and Rosehill are not running due to fallen overhead wires near Carlingford.
Passengers are being advised to make alternative travel arrangements.
Trains are not running between Parramatta and Richmond, or between Parramatta and St Mary's on the T1 North Shore and Western Line, T5 Cumberland Line and Blue Mountains Line, due to severe weather conditions causing power supply issues.
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Replacement buses have begun running between Blacktown and Richmond.
The NSW State Emergency Service (SES) has advised people impacted by storms to stay indoors and move cars under cover and away from trees.
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