Rain is on the way for the North Island. Photo: 123RF / MetService
MetService is warning of heavy rains and possible thunderstorms in Coromandel, Waikato, Bay of Plenty, Rotorua and Gisborne.
The forecaster said localised downpours of up to 40mm an hour may affect some areas from 3pm on Monday.
It said the risk of downpours west of Rotorua would ease by 9pm, but continue further east until midnight.
The downpours could happen with or without thunderstorms. MetService said the rain could cause surface flooding in low-lying areas.
Further south, there was a heavy rain warning issued for Waitomo, Taumarunui, Taihape and southern Taupo, and a watch in force for eastern Taranaki, inland Whanganui and the Tararua Range, north of Wellington.
About 50mm of rain fell on Mt Taranaki overnight, while the Tararua Ranges had seen about 65mm already.
The rain followed a week of heat and sun which prompted MetService to issue heat warnings.
MetService meteorologist Clare O'Connor earlier told Morning Report the North Island was in for a wet couple of days.
"Particularly this afternoon for those living along that northern coast from northern to eastern Bay of Plenty, we might see a few downpours along there. Then Tuesday, a little dry overall, but the rain does return to the North Island before then shifting back down to the South Island."
Rain was also forecast for the South Island on Monday.
"The next couple of days are looking to dry out," O'Connor said.
"But looking forward to the later half of the week, we do have another low approaching from the Tasman Sea which will bring rain again, at least to the west of the South Island."