Sydney hit over by more than 20,000 lightning strikes during storm

More than 22,000 lightning strikes and a waterspout were detected during last night’s storm in Sydney, according to Weatherzone.

Lightning struck across 100km of Sydney during the 12-hour storm, which ended at 3am on Wednesday.

A waterspout – a large vortex of water spinning above a body of water – was spotted over Dee Why just before 7pm, which was most likely caused by the unusually warm ocean water, Weatherzone said.

Over 22,000 lightning strikes and a waterspout were detected during last night's storm in Sydney, according to Weatherzone. — A waterspout is a large vortext of water attached too two clouds on either end, they usally form over a body of water. (Weatherzone)

Grey skies are expected to gloom over Sydney following the storm, but the clouds are expected to head up the coast towards the Lower Hunter region – sparing Sydney from another lashing of more than 120mm of rain, flash flooding and damaging winds.

The storm blacked out more than 600 residential properties while the SES received 377 calls for assistance over 24 hours. Power outages continued until this morning when electricity was restored to Avoca Beach and its surrounding suburbs at 7.20am.

Sydney’s southern suburbs were hit hard by the storm in the early morning, with trees and powerlines taken out.

The roof of one family’s home in Yagoona, Bankstown was flattened by a tree.

A families roof was flattened by a tree, which had fallen during the storm (Nine)

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Severe storm warnings for the Lower Hunter have been revoked by the Bureau of Meteorology as the storm tracks north, but residents have been told to monitor storm conditions following 50-80mm of rain in Lake Macquarie and Newcastle.