Some Horsham residents in Victoria's west will need to rebuild their homes after a "fierce tornado" ripped through the city's north early on Monday morning.
Strong winds at 1:00am tore roofs off houses north of Wavell Street, snapped tree trunks and left sheets of metal wrapped around trees.
More than 70 houses were damaged and the clean-up is expected to take more than 24 hours.
The damage was caused during an intense weather event that probably only lasted a few minutes, Diana Eadie from the Bureau of Meteorology said.
"Preliminary investigations suggest a short-lived but fierce tornado impacted parts of Horsham in the early hours of the morning," she said.
"At this stage, the damage is consistent with an EF1, which is wind strengths between 138 and 177 kilometres per hour.
"This was a very short-lived system — the entire event is likely to have occurred in less time than it takes to boil a kettle."
Trees down and trampolines blown away
The tornado has been described as one of the most-damaging weather events in Horsham's recent history.
Residents at four properties have been relocated, the Victorian State Emergency Service (SES) said, and the local council has organised accommodation for one homeowner.
Victorian Police Minister Lisa Neville said the residents of homes that are now uninhabitable were being supported.
"It's just a horrific experience to live through," she said.
Two people were temporarily trapped inside a house after the roof of a neighbour's home blocked their door, the SES said.
The SES responded to more than 97 requests for help by 2:30pm, including 76 calls reporting building damage.
"We've seen roofs ripped off, we've seen tiled roofs, we've seen tin-sheeted roofs, but we've also seen loose objects around people's homes," SES chief officer of operations Tim Wiebusch said.
"Trampolines have ended up yards away from where they were originally in people's backyards, and we've also seen trees down and even some crop damage as well."
More than 3,200 residents lost power but it was all restored by 10:00am, electricity company Powercor said.
Emergency service crews from Bendigo, Hepburn, Gisborne and Hamilton helped relieve SES volunteers in Horsham.
Horsham Police sergeant Troy Curran urged people to be patient as authorities respond to the damage.
