Rainfall of this intensity could cause both surface and flash flooding, MetService warned. Photo: RNZ / Rebekah Parsons-King
Severe thunderstorms could break up calm skies in the lower half of the North Island on Tuesday afternoon.
Weather forecaster MetService said thunderstorms were expected in Waitomo, Taumarunui, Hawke's Bay, Taranaki, Taihape, Whanganui, Manawatu, Tararua and Wairarapa.
It said the storms could be severe between 2pm and 9pm and localised downpours could produce 25 to 40mm/h of rain.
Rainfall of this intensity could cause both surface and flash flooding, it warned, especially in low-lying areas such as streams, rivers or narrow valleys.
Drivers should also be mindful of hazardous conditions caused by thunderstorms.
MetService said heavy rain could cause poor visibility, surface flooding on the roads and slips.
Meanwhile, some regions further north are also expected to receive heavy rain on Wednesday.
Coromandel is expected to receive 100-140mm of rain around the ranges between midday Wednesday and midday Thursday. But the forecaster said rain may continue past then.
Periods of heavy rain are also expected in parts of Auckland, Northland and the Bay of Plenty on Wednesday.