A man has died after a tree fell onto a car at Mount Buller in Victoria's north-east.Emergency services, including Victoria Police and Advanced Life Support paramedics, responded to the single-vehicle incident about 9:15am on Monday.Police believe the vehicle was travelling along Mount Buller Road when a tree fell onto the car.The female driver was taken to Wangaratta Hospital by road in a serious condition with an upper body injury. A male passenger, who is yet to be formally identified, died at the scene.Emergency services attended the scene as police began investigating the circumstances surrounding the incident.Police said the investigation remained ongoing and a report would be prepared for the coroner.Mount Buller Road is closed in both directions due to the incident, with significant delays expected.State Emergency Service (SES) crews in the state's north-east had 80 requests for assistance overnight.SES Hume regional duty officer Michael Isbister told ABC Goulburn Murray Breakfast that crews had already completed five water rescues."We had one member of the public wake up and be completely surrounded by water," he said.With record-breaking rainfall totals across the region, the SES is warning residents to stay alert as more rain comes through."The ground is extremely wet, so it's going to [make] these rivers flow and rise really quickly," he said.A driver and passenger were rescued after their vehicle became stuck in floodwater at Lexton in Victoria's west, early this morning.The incident occurred along the Sunraysia Highway north-west of Ballarat.Flooding has forced the closure of a number of roads across the Pyrenees Shire, including at Avoca, Lexton and Beaufort.More than 135 millimetres of rain has fallen over parts of Ballarat and surrounds since midnight.