The State Emergency Service is responding to around 50 calls for assistance after heavy rain caused minor flooding in parts of the Hunter this morning.
The heaviest falls of between 30 and 80 millimetres were along the coast between Lake Macquarie, Newcastle and Nelson Bay with 60 millimetres recorded at Merewether between 6 and 7 am.
Flash flooding caused problems for motorists this morning in parts of Newcastle but all roads are now clear.
Hunter region SES controller Greg Perry says most of the calls this morning have been for leaking roofs.
"Requests for assistance that we have taken totals 49 and the bulk of those being taken in Newcastle and Lake Macquarie," he said.
"The main message as we move through storm season is make sure that your gutters are clean for the short amount of time that it takes to give them a quick clean out will save you a lot of trouble later on if you're calling an insurance company to make a claim, especially if you're had water coming down inside your house."
© ABC 2013
21:52 EST Parts of Sydney and the Blue Mountains have been blanketed by large hailstones as a severe thunderstorm moves across the area.