The MetService has issued a severe weather warning for eastern parts of the North Island, including the Coromandel Peninsula and Bay of Plenty.
The warning also extends to Marlborough at the top of the South Island.
MetService says a moist, unstable, northerly flow covers the northern half of the North Island with heavy showers and possible thunderstorms expected on Wednesday.
Intense rainfall is possible in Coromandel, Bay of Plenty and Gisborne at night.
