Roofs have been torn off buildings and thrown up to half a kilometre away by what is believed to have been a tornado that tore through parts of south-west Victoria.

Key points: Lake Purrumbete Caravan Park, in Victoria's south-west, bore the brunt of the weather event

Lake Purrumbete Caravan Park, in Victoria's south-west, bore the brunt of the weather event An SES member described the scene as 'horrific' and the worst damage he had seen

An SES member described the scene as 'horrific' and the worst damage he had seen There were only a handful of people staying at the caravan park, with minimal injuries reported

Emergency services were kept busy overnight as a storm left a trail of damage from Camperdown to Lake Purrumbete.

The Lake Purrumbete Caravan Park bore the brunt of the weather event.

Owner/manager John Clements said about 40 cabins at the park had been "completely demolished", with about 20 more damaged.

Mr Clements said the park would be closed for several weeks.

"We'll just rebuild," he said. "We'll get back on the horse," he said..

"Definitely closed for at least a couple of weeks. But hopefully it will be quick clean-up."

Camperdown SES controller Colin Brian said SES volunteers had to cut their way through half a dozen trees that had fallen onto roads to get to the park.

"We worked our way through that and found a horrific scene. It's something I've never seen before," Mr Brian said.

"There were cabin [roofs] blown away, boats in the middle of the road, trees down everywhere.

"Hundreds of metres, half a kilometre some of the stuff was blown. It was just bedlam, it's hard to describe.

"I haven't seen anything like that in my time at the SES. [The caravan park] is just gone."

The remains from where a cabin once stood at Lake Purrumbete Caravan Park. ( Facebook: Camperdown SES )

Mr Brian said it was fortunate only "five or six people" were at the caravan park, so injuries were minimal.

"One person … got hit on the head, and one got a minor cut," Mr Brian said.

No one has been able to confirm definitively that it was a tornado, but Mr Brian said that description made sense.

"There's trees [blown down] one way and then trees [nearby blown down] facing the other way," he said.

"There was damage to houses before you get to the caravan park — roofs off, trees down [and it's all in] one strip through the west side of the lake."

SES volunteers described the damage as unlike anything they'd seen before. ( Facebook: Camperdown SES )

Local businesses have already contributed to the clean-up effort, providing skips for rubbish and containers for people to store their belongings in.

From out of nowhere

At the nearby Lake Edge Cafe, owner Lois Dupleix said she was counting her blessings.

The devastation at Lake Purrumbete Caravan Park following what is believed to be a tornado. ( Facebook: Camperdown SES )

"There's a large verandah on the front of the cafe which is in many pieces. I'm so in love with my old building and it survived, so I'm rapt," Ms Dupleix said.

"But my son lost a shed, all his office equipment, a caravan that's just a pile of pulp in a tree.

"Very luckily a guy that was sleeping in it [the night before] left — a German backpacker sleeping in it the night before — who would have had an interesting experience to go home with.

"My heart goes out to the caravan park and the next door neighbours who've got the roof off their house. We've still got houses and things so we're all still good, but a bit of work ahead of us.

"Nobody knew it was coming, there was no real warning, but kaboom. It was just a massive storm."

But every cloud has a silver lining.

"We wished for rain and got some, so that's the good news," Ms Dupleix laughed.