article: Sydneysiders already reeling from a three day 'cyclone' were hit again on Saturday, as the city was pummelled by a massive hail storm. Marble-sized hailstones, some up to 2cm in diameter pounded multiple suburbs in the city's east and west on ANZAC Day, coating streets and backyards in sleet despite only lasting for around three hours. Saturday's freak weather could be explained by constantly changing atmospheric conditions and bursts of ice-cold air, said Bureau of Meteorology NSW Manager of Weather Services, Andrew Treloar. Scroll down for video . Many took to social media on Saturday to post incredible pictures of residents tobogganing and snow boarding down streets in Newtown . According to Mr Grose, a large storm with an East Coast Low have always occurred within Australia, passing through every few years . But there's a longer term story behind the recent spate of wild weather, one scientist said. 'Climate has been changing in recent decades and will continue to change throughout this century and beyond,' CSIRO, Research Scientist Michael Grose told Daily Mail Australia. According to Mr Grose, Saturday's storm was the result of an East Coast Low, which is also known as an extratropical cyclone. This type of storm has always occurred in Australia, passing through every few years, however changes to the frequency and intensity are possible due to climate change. 'Increases in temperature and rising sea levels are the most clear changes in the climate due to human influence,' he said. A combination of hail and water at Enmore in Sydney's inner-west, almost completely submerged a line of cars . Several cars were submerged in the flood waters following the flash flooding that struck the city . Snowing in Sydney? Sydney's west was hit by snow-like hail after the storm travelled east from the Blue Mountains . Parramatta Stadium was blanketed with hail, delaying kickoff but making for an amazing scene . 'The Bureau provided thunderstorm warnings of hail and damaging winds for Regional areas from 11am Saturday morning,' Mr Treloar said. Blackheath residents in the Blue Mountains, about 100km west of Sydney, reported hailstones up to 2cm in size, while social media users shared surreal images of snowmen and even snowboarders on the streets of Sydney. Seven buildings collapsed in western Sydney after they were damaged by the storm, with Fire and Rescue crews still working to assess damage. A woman also had to be rescued from her car after she became trapped in the rising waters at Zetland in Sydney's inner-east. Marble-sized hailstones, some up to 2cm in diameter, pummelled multiple suburbs in the city's east and west on ANZAC Day . A woman had to be rescued from her car which had become trapped in flood waters following Saturday's severe storms . She appeared safe and calm as police and fire and rescue crews assisted her at Zetland in Sydney's inner-east . Hail is seen on the road in the suburb of Alexandria. Large areas of Sydney have been hit by a hail storm this afternoon . Superintendent Paul Johnston from Fire and Rescue NSW told Daily Mail Australia that the incident was just one of many flash flooding events that emergency services had attended from 4pm. 'At the height of the storm we had two hundred calls in the system, mostly about flooding in people' homes and businesses, rescues from flash flooding - in the inner city they're not as dangerous because people are just trapped in their cars and not at risk of being swept away - and automatic fire alarms,' Supt Johnston said. 'The highest rainfalls recorded during the event were 60mm at Prospect Reservoir and 53mm at Blacktown, much of which fell within 1 hour. There were also reports of flash flooding in the Metropolitan area,' Mr Treloar said. 'Thunderstorms with large accumulations of hail have been noted before in Sydney and surrounding areas during the Autumn months.' Streets and backyards were transformed into snowfields across Sydney and the Blue Mountains. Pictured Maroubra in Sydney's east . An unstable air mass over the top of New South Wales is understood to have generated the east-moving storm. Pictured: Kingsford in Sydney's eastern suburbs . A police spokesperson told Daily Mail Australia that two factories at Huntingwood, in western Sydney, have collapsed due to the weather . Marble-sized hail stones pummelled various suburbs in Sydney and the Blue Mountains . NSW Ambulance tweeted: 'Luckily no one injured in this building collapse at Eastern Creek. Be careful if on the icy roads' Ominous looking storm clouds rolled into Sydney Harbour in the afternoon as the sky turned form blue to black and then a strange white . The NRL match between the Sydney Roosters' and St George Illawarra at Allianz Stadium in Sydney had to be temporarily suspended due to hail and lightning . Heavy rain, wild winds and hails stones transformed the Blue Mountains and parts of Sydney into snowfields on Saturday evening . Warnings stated that 'large hailstones, heavy rainfall that may lead to flash flooding and damaging winds' were predicted . State Emergency Services issued cautions and advice to residents affected by the storm on their social media pages . Hail stones piled up behind a door or a window during the storms, which only lasted until 7pm . Hail covers a road and vehicle in the suburb of Alexandria just after the storm passed . Twitter and Instagram users captured images of the storm: Lightning strikes in Sydney as the storm rolled in . Backyards and streets were transformed into snowfields within minutes by the heavy rain and hail .
highlights: After the 'storm of a century' finally dissipated last week, Sydneysiders believed the worst was over .
  Then on Anzac Day large hailstones blanketed Sydney and the Blue Mountains in a ferocious downpour .
  Hailstones of up to 2cm were reported in some areas, as the storm transformed parts of the city into 'snowfields'
  The weird weather conditions can be attributed to some degree to climate change, according to CSIRO .
  Seven buildings, including five 200m long factories, collapsed under half a metre of hail in western Sydney .
  State Emergency Services attended over 800 calls for help before the storm cleared at around 7pm .
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