The New South Wales State Emergency Service has received more than 130 calls for help after very heavy rainfall caused flash flooding south and south-west of Sydney. The storm was expected to move north, where it could cause further flash flooding around Hornsby. The SES says at least four of the calls for help involved cars trapped in floodwaters in the Sutherland Shire. Phil Campbell from the SES says people should avoid driving on flooded roads. Sydney Airport expected some delays after the threat of lightning forced it to bring ground-handling staff indoors.