The Bureau of Meteorology earlier issued a weather warning for the New South Wales capital.
Severe thunderstorms were detected on the weather radar near Bankstown, Engadine, Fairfield and Liverpool.
They were forecast to affect Parramatta, Sutherland, Sydney City, Sydney Airport, Sydney Olympic Park and the Sydney Harbour Bridge by 5.25 pm and Manly, Maroubra, Randwick and waters off Bondi Beach by 5.55 pm.
However, the severe storm warning for Sydney was cancelled just before 6pm as the weather proved to be ferocious, but brief in duration.
People have been warned to keep clear of any downed powerlines and flooded creeks.
Power outages have been reported in several suburbs, with Ausgrid saying they were working to restore it.
A severe storm warning has also been cancelled for parts of northern NSW.
The wet and stormy conditions are expected to continue in the coming days across widespread parts of Australia.
The remainder of the country is expected to remain dry due to a high.
This includes a severe thunderstorm warning for parts of NSW, with the potential for damaging winds, large hailstones and heavy rainfall.
Residents are asked to secure loose items and call 13 13 88 if they see fallen powerlines.
The thunderstorms are expected to last into Saturday and the rain is likely to continue in some areas until early next week.
Weatherzone says that while just some storms are considered severe, they all contain lightning.
If you hear thunder, the best thing to do is stay inside until the storm has cleared.
“The weather predictions for the next week are ideal for thunderstorm asthma,” Victoria’s AMA president Dr Roderick McRae told Today yesterday morning.
“Anybody with a known diagnosis of asthma, please take your preventative medications.”
A tornado hit Clear Creek, north-east of Bathurst, whipping up debris and damaging homes.
A second tornado was recorded in Narrabri several hours later and although locals reported it to be fierce, no major damage was recorded.
“This tornado (on Thursday) is part of a prolonged thunderstorm outbreak in eastern Australia, which has been going since Tuesday and is likely to last until Saturday,” Weatherzone said.