Severe weather warnings are in place for central and northern parts of the North Island.
MetService says thunderstorms are expected on Thursday evening in Northland, Auckland, Great Barrier Island and the Coromandel, with wind gusts in excess of 120km per hour.
Heavy rain is expected in the central North Island.
Worst affected areas are expected to be the hills and ranges from Mount Taranaki to Raglan and across to the central high country, as well as the ranges of eastern Bay of Plenty.
About 100mm of rain is possible in those areas.