A Waikato mum hid in the bathroom as a loud buzzing headed towards her house, while her neighbour stood in the hallway of her shaking home as a tornado shook the outskirts of Hamilton this afternoon.

The farms in Ruakura were in the direct path of a tornado that ripped through the properties sweeping up soil, scattering the rubbish in two skips, lifting large sheets of corrugated iron, wooden pallets, a trampoline, washing and other outside toys high into the sky before dumping them meters away in neighbouring paddocks.

As the twister struck just before 1pm, people as far as Hamilton's CBD quickly took out their phones to capture the rare moment.

Shiela Flor, who was inside one of the farmhouses on the farm with her young children, said she could hear a large buzzing noise before the tornado struck.

"I raced to hide in the bathroom. It was a buzzing noisy sound. It wasn't very big but it was very strong."

"You can see the trash flying around. It was really scary because of the sound."

Her children's trampoline was swept up to tree height before being deposited 10m away in a neighbouring paddock, washing was scattered all over the fields and a large door mat from the deck had been hurled up in a tree.

She watched as rubbish that had been in bins at one end of the farm blew past her home, landing all over the place.

Farm owner Rebecca Davison was in her house next door when her small dog alerted her to a noise.

Half-way up the Holland Rd farm, the tornado had picked up dirt and she could see it spinning around.

"And then I could hear a big loud ringing noise. Then all of a sudden the wind picked up and you could see a big wall coming towards you."

"It threw roof iron into the paddock - that's when I realised it was coming straight towards the house. The whole house was shaking and it was still quite far away."

She quickly moved away from the windows and stood in the hallway as she felt the tornado go over the house.

"It moved quite fast. I have never seen anything like that before ... It was quite surreal," Davison said.

Kurt Hogwood was relaxing in his spa on the other side of Holland Rd when an intense gust of wind came from nowhere.

Dust, dirt, leaves and sticks flew past him and lasted about 10 to 15 seconds.

Eureka dairy farmer Sam Owen was heading west along State Highway 26 in his tractor when he spotted a strange cloud formation in the distance.

"I stopped at the intersection there and got out of my tractor because I was on my way to do some work and took three photos," he said.

"The first one sort of shows its spoke coming down."

The next two photos show the dramatic moment the tornado rips, what he believes is, soil out from the earth.

Owen watched the twister for about two or three minutes.

There were also reports of tornadoes forming in other areas.

Tauranga man James Grafas and his 10-year-old son Isaiah were heading back home from Mount Maunganui at about 2.30pm when he spotted a funnel-shaped mini-tornado.

"It definitely didn't look like an ordinary dark cloud formation. I handed my cellphone to my son and he started to video it for me and we continued to watch it as I drove past the Tauranga Auto Village.

Weatherwatch.co.nz has warned more isolated tornadoes were possible this afternoon in the upper North Island due to instability in the atmosphere, plus warmer than average weather.

There was also a risk of isolated thunderstorms, downpours and surface and flash flooding in localised areas, the forecaster said.