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SYDNEY - One man was injured by lightning, at least 12 cars were swamped by stormwater and 19,000 homes and businesses were blacked out as summer thunderstorms dumped heavy rain on Sydney yesterday.
The storm systems moved across Sydney from south to east with more than 20 millimetres of rain recorded in the city's south-west.
The storm and its associated flash flooding and lightning caused serious delays for people trying to travel by road, rail and air.
Flights due to depart from Sydney Airport between 2.40pm and 3.45pm AEDT (4.40pm and 5.45pm NZ time) were delayed, with ground crews unable to work due to lightning strikes.
Sydney rail commuters were warned to expect delays on the Bankstown, Inner West and South coast lines with services between Campbelltown and Macarthur affected this afternoon.
Roads were clogged with traffic, with visibility poor and conditions dangerous due to the weather.
Integral Energy said 19,000 homes and businesses were blacked out about 3.30pm AEDT (5.30pm NZ time) and 4400 homes remain without power tonight.
In Sydney's south-west, a 52-year-old man was hit by lightning at Narellan Road, Campbelltown at 3.20pm AEDT (5.20pm NZ time), a NSW Ambulance spokesman said.
The man was taken to Campbelltown Hospital where he is in a stable condition.
Nearby at Menangle, commuters watched as cars were swamped with water outside Broughton Anglican College.
A police spokesman said one of the vehicles was washed into a culvert, causing water to back up and flood Menangle Rd, at Menangle. No one was injured.
"All reports from local police are that the students from that school are not in any danger or under threat," a police spokesman said.
The college has cancelled today's classes.
State Emergency Service (SES) spokesman Steve Delaney said flash flooding was recorded at Camden, Liverpool and Parramatta as the storm crossed the metropolitan area.
He said small hailstones were recorded in the Campbelltown area.
A Bureau of Meteorology spokesman said the storm system stretched from Sydney to the Victorian border, the central west slopes and central tablelands.
Canberra was lashed on Tuesday night by a severe hail storm which closed schools, government departments and a university as road crews cleared hail drifts up to one metre deep around city streets.
- AAP