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 2 cm 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 7 pm .