Authorities declared a natural disaster Saturday in parts of eastern Australia where gales have toppled trees and knocked out power to tens of thousands of homes. Heavy rain, lightning and winds as strong as 100 kph have swept across Sydney and other areas of New South Wales since Wednesday.

Wild weather is expected to continue through the weekend, with ongoing thunderstorms on the east coast and a tropical cyclone developing just off the coast of Western Australia.

Footage shows a dramatic lightning storm above the Sydney Olympic Park in New South Wales, Australia, as at least one person was killed in the storm. Officials said that an unstable airmass combined with an upper trough produced wild weather across large swathes of the state late Wednesday.

Wednesday’s destructive storm was lit up by flashes of lightning, with more than 70,000 strikes recorded within 100 kilometres of the CBD.

A huge line of storms crossed New South Wales overnight, causing power outages, flash flooding and almost 2 million lightning strikes.

Sydney and other parts of New South Wales were hit by fast moving storm, with thunder, lightning, heavy rains and winds that left some suburbs blacked out. This footage illustrates powerful lightning strike during severe thunderstorm near Sydney Olympic Park.

Footage shows a dramatic lightning storm seen above Sydney in New South Wales, Australia, as at least one person was killed in the storm. Officials said that an unstable airmass combined with an upper trough produced wild weather across large swathes of the state late Wednesday.