Severe thunderstorms and tornado warning for North Island

The forecasted trough  over the North Island, as seen in MetOceanView.

The forecasted trough  over the North Island, as seen in MetOceanView.

An upper cold trough is forecast to move across New Zealand's North Island tonight, which will bring with it thunderstorms and a risk of tornadoes.

If tonight's storms are well developed by the time they hit the shoreline, wind speeds on the west coast of the North Island may exceed 110 km per hour. 

There is also the possibility of a few tornadoes forming. 

The New Zealand MetService are warning people to watch out for falling trees and power poles, to secure loose items such as trampolines, and to expect localised flooding.