Sydneysiders have been warned to brace for large hail and wild winds as severe thunderstorms develop in New South Wales this afternoon.
A severe storm was detected near Leppington and Bringelly, in Sydney's south-west, and is set to produce hailstones and damaging winds as it moves east.
"We've seen a lot of storm activity brewing in the last couple of hours," meteorologist Angus Hynes from the Bureau of Meteorology said.
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"Now imminently moving across the west of Sydney."
"We've just seen those warnings be expanded to include the entire Sydney metro area, and at the moment, there are two storm systems in particular that we're watching pretty closely," he added.
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The storms and rain showers are developing following a hot day in which Sydney recorded a high of 34.7 degrees at the airport and in excess of 35 degrees out west.
Earlier today, Weatherzone had forecast that unstable weather was likely to develop as a cold front and low-pressure trough swept over the state and collided with a "much warmer" air mass.
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"An upper-level trough passing over southeastern Australia on Friday will also help to destabilise the atmosphere, resulting in an outbreak of thunderstorms across central and northeastern parts of the state," the site reported.
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"Isolated supercell thunderstorms are also possible on Friday, particularly over central eastern NSW," it added.
"If these supercells do form, they may cause destructive wind gusts in excess of 125km/hr and giant hail measuring more than 5cm in diameter."
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