Thousands of Victorian homes could be left without power overnight as a wild thunderstorm sweeps across the state.

A severe thunderstorm warning has been issued on Tuesday afternoon for Bendigo, Maryborough, Castlemaine, Kyneton, Ballarat, Bellarine Peninsula and greater Melbourne.

Damaging winds, large hailstones and heavy rainfall are likely, the Bureau of Meteorology alert said.

Thunderstorm cells are moving southeast and may lead to flash flooding over the next several hours.

“Park your car undercover and away from trees,” the bureau cautioned.

“Stay inside if conditions outside appear dangerous.”

Some 24,000 power customers across central and western Victoria are already off the grid after the storm brought down trees and damaged the network.

Powercor, which supplies power to 1.2 million Victorian homes and businesses, said a significant amount of lightning had also impacted the grid and its crews are working to fix more than 200 faults.

“Ballarat and surrounding communities are the hardest hit areas, with around 13,000 customers without power,” a Powercor spokesman said in a statement.

“Other areas impacted include Castlemaine, Bendigo, Hamilton, Ararat, Horsham and Maryborough, as well as some of the western suburbs of Melbourne.

“Our crews will continue to work to have power restored throughout the afternoon and evening, but given the volume of faults and the damage sustained, some customers will be without power overnight.”

Buses are replacing trains along the Craigieburn line from Broadmeadows to Craigieburn due to a lightning strike affecting equipment.

Metro Trains warned the replacement buses could take up to an hour to arrive while noting trains were operating as normal from Flinders St to Broadmeadows.

Source: AAP