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Sydney has been rocked by hailstorms and thunder, which have caused flight cancellations and flash flooding to affect light rail services.
Thunderstorms broke out this afternoon in Sydney, with lightning strikes and massive hail storms falling on houses in the city's west, as meteorologists warn the rest of the country will be hit by more storms later this week.
An outbreak of potentially severe thunderstorms is forecast to hit eastern Australia from this afternoon until Wednesday, according to the Bureau of Meteorology.
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Almost 4000 people were hit by power outages as of 3.30pm, with outages in Hurstville and North Manly reported to Ausgrid.
Some flights into and out of Sydney were delayed or cancelled.
"Due to storm activity, there have been some flight delays and cancellations," a Sydney Airport Spokesperson said.
"We encourage passengers to check with their airline regarding the status of their flight."
The Bureau of Meteorology said a severe thunderstorm was producing heavy rainfall that may lead to flash flooding across Sydney, from the Olympic Park at Homebush to Bondi Beach.
They said the thunderstorm was moving northeast, and likely to hit Manly and St Leonards, before moving over Dee Why throughout the afternoon.
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Images shared with 9news.com.au showed massive hailstones falling in Emu Plains and near the Blue Mountains.
Hail was also reported on Sydney's Northern Beaches and Inner West.
Sydney's light rail was also disrupted by flooding on the tracks, with the L2 Randwick Line and L3 Kingsford Line closed between Moore Park, Randwick and Juniors Kingsford.
It is now running again.
Thunderstorms are expected in some parts of the country every day this week, thanks to a series of troughs and low-pressure systems.
Storms were already brewing over southern and eastern Australia this morning, meteorology service Weatherzone said.
A low-pressure system is expected to drift eastward from WA, bringing storms to the rest of the country on Thursday and Friday.
They could bring destructive winds, large hail, and downpours of rain.
Both Sydney and Melbourne are set for several days of showers.
A mass of hot air concentrating above Central Australia is driving some of the turbulent weather.
According to Weatherzone, daytime temperatures in South Australia's north could reach the mid-40s on Wednesday and Thursday.
Overnight minimum temperatures will also be higher than usual, and could challenge heat records for this time of year.
