Parts of Sydney are experiencing flash flooding this morning after heavy rains hit the city, with one area receiving almost a month's rain in 24 hours. A severe weather warning has been issued for Sydney, but the heavy rain front that passed over the city this morning is predicted to ease this afternoon. Main roads in the city center such as Syd Einfeld Drive in Bondi are flooded, causing traffic issues. Bureau of Meteorology forecaster Zhi-weng Chua said Gosford, on the Central Coast, received 123.8mm over the past 24 hours. Its monthly average for March is 149.9mm. While Lucas Heights, in the city's south-west, has received 54mm since 9am this morning. "The highest rainfall received in the last 24 hours to 9am Sunday has been at Wyoming with 134.5mm," he said. "The wetter part of the day we expect will be the morning and early afternoon. We do expect shower activity to continue into Monday. "We've had now two flood rescues, one at Wyong and one at Gosford this morning and both involved cars attempting to drive across flooded roadways." Mr Chua said there were currently no warnings in place. "It is heavy rainfall but it hasn't been enough to exceed the threshold."We are seeing shower activity, mostly along the central coast and Sydney coast." NSW SES spokesperson Neil Wilblin said it had been a busy morning for volunteers. "We've had about 260 call outs mainly across the metropolitan area," he said. "With these widespread showers most of the jobs have been in relation to roof damage, roof leakage, ceilings leaking, skylights leaking. "On the central coast, emergency workers conducted two rescue operations.