Weather: Fierce storm hammers Sydney

Mount Brandon Road at Jerrara Dam is cut by flood waters west of Kiama (AAP)
Mount Brandon Road at Jerrara Dam is cut by flood waters west of Kiama (AAP)

Heavy rain and hail bombarded Sydney overnight, with flash flooding causing havoc across the CBD.

Emergency services were flatout with callouts after motorists ignored pleas to stay at home.

For 30 minutes the heavens opened above the CBD and the rain came down. It turned stairwells into waterfalls, and streets into raging torrents.

Drivers were left to take their chances, navigating down roads turned into waterways.

The city was bursting at the seams. With the rain came hail, halting traffic.

The storm had already turned the Blue Mountains white, and hail the size of golf balls fell further north in the Hunter Valley.

There were more than 600 calls for help, including 34 people who were stranded in floodwaters.

"I just can't emphasise enough how risky a proposition it is driving through floodwaters," says Greg Newton of the State Emergency Service.

The storm left behind hundreds of thousands of dollars of damage.

Further west, a mini-tornado ripped through Dubbo.

The wild weather is now moving south, continuing to cause damage, with warnings in place for the next 24 hours.

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