Severe thunderstorms with large hailstones and damaging winds are forecast for the New South Wales (NSW) Central Coast, the Australian Government Bureau of Meteorology (BOM) said Tuesday. The BOM on Tuesday afternoon issued a severe thunderstorm warning for people in the northern parts of the state, including the Northern Rivers, Mid North Coast, Hunter, Northern Tablelands and parts of the North West Slopes and Plains Forecast Districts. \"Severe thunderstorms are likely to produce large hailstones and damaging winds in the warning area over the next several hours,\"it warned. Locations including Lismore, Grafton, Coffs Harbor, Port Macquarie, Taree, Newcastle, Gosford, Cessnock, Maitland, Armidale, Tenterfield and Tamworth could be affected by the thunderstorms, the warning said. NSW Fire and Rescue Superintendent Ian Krimmer said strong winds were also causing chaos in Sydney and crews were responding to the incidents. \"Right across the Sydney metropolitan area we have numerous reports of trees down, wires affected. We have several roofs being impacted on buildings. We\'ve got a loose window in Pitt Street. We \'re checking out a crane at Bankstown,\" he told Australia\'s Fairfax Radio on Tuesday. NSW electricity supplier Ausgrid said the company\'s emergency crews were trying to get power back in several areas. NSW ambulance said three people have been taken to hospital after being hit by a falling tree in Engadine in Sydney\'s south.