The NZ WeatherWatch warns more tornadoes could strike in the next 24 hours in Auckland after a "relatively minor" tornado caused fences and trees to fall Sunday afternoon. Houses' windows were smashed and powerlines went down, too, as the tornado swooshed in the city.

WeatherWatch analyst Richard Green told the New Zealand Herald the tornado was "relatively minor" compared to May's twister in Albany, which killed 37-year-old Benedict Dacayan.

The Herald reported that the NZ Fire Service estimated the twister to be a kilometre in scope. It added a house was struck by lightning and at least 13 properties were damaged when the tornado ripped through Avondale and Te Atatu South at about 1pm.

The intersection of Ash Street and Wairau Avenue, Avondale were the roads perceived to have sustained the worst damages.

"Fortunately it was short lived because if it had been a longer electrical storm, who knows what chaos could have resulted," Green said.

Thunderstorms had been forecast for Auckland Sunday afternoon, but not tornadoes.

"The system that was being looked at just revved up a little more as it passed over Auckland, which produced the tornado... It was basically just very warm air and cold air mixing," explained Green, adding that another weather disturbance was on its way to New Zealand area of responsibility. There is a risk of further tornadoes in western areas of the North Island for the next 24 hours due to this approaching weather system.

Auckland coast guard duty officer Katherine Andrews told the Herald the tornado ripped the masts off two yachts and caused another to run aground.

"The wind just picked up like you wouldn't believe," she said.

Meanwhile, MetService has issued severe weather warnings for Southland, Otago, Wairarapa and Hawke's Bay and said gale force winds could spread over much of the North Island on Monday.

MetService advised farmers in affected areas to take necessary measures to protect their stock.