Hundreds of thousands of Victorians were stranded without power on Thursday and a man died as major storms lashed the state, at the same time as a cold snap brought snow and warnings of electricity outages in NSW.

Police found the body of the man, believed to be in his 60s, in a submerged car in floodwaters near Woodside, in south-east Victoria on Thursday afternoon, as emergency services scrambled to respond to more than 50,000 calls for assistance.