Multiple domestic flights to and from Sydney Airport have been delayed or cancelled after a thunderstorm ripped through the city.
The Bureau of Meteorology warned of a thunderstorm across Sydney and surrounding areas on Monday morning, including the potential for flash flooding as a result of heavy rainfall.
Before 11am on Monday, about 210,000 lightning strikes were detected within 200km of Newcastle.
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Four people were injured when a lightning struck a tree they were standing under near the entrance to the Botanic Gardens of Sydney on Monday afternoon.
The wild weather led to the tarmac at Sydney Airport being closed for two hours and a number of flights being cancelled or delayed.
Some flights arriving in Sydney from the Gold Cost, Melbourne and Canberra were cancelled after 2pm.
Fights departing Sydney arriving in Adelaide, Hobart, Brisbane, Melbourne or the Gold Coast were also cancelled.
Sydney Airport advised passengers to check the status of their flight with their airline.
Qantas said three of its flights were diverted to Canberra or Brisbane during the storm.
A Qantas Sydney-Perth return flight and three other flights between Sydney and Melbourne were also cancelled.
By 4pm, the bureau cancelled its thunderstorm warning and said rainfall had eased around Sydney.
“The immediate threat of severe thunderstorms has passed, but the situation will continue to be monitored, and further warnings will be issued if necessary,” it said.
Nearly 50mm fell in an hour at Kings Langley, in the city’s northwest, while Belrose received 34mm in two hours.
Near-stationary storms also caused downpours over Blacksmiths in Newcastle, with 65mm falling in less than six hours.
-With AAP