People in the Coromandel and Bay of Plenty areas are being advised to prepare for another dousing of heavy rain.

A complex low over the Tasman Sea is expected to move eastwards onto the North Island from late Wednesday to Friday, and its associated fronts move southeastwards across the Island.

"These features should bring a period of rain to much of the Island, especially in the north and east. A period of strong east to northeast winds is also expected ahead the fronts," says the MetService.

"The heaviest rainfall is expected in Coromandel Peninsula, where a heavy rain warning is now in force.

"A heavy rain watch is in force for northern Auckland, Western Bay of Plenty, the Kaimai Range and northern Gisborne.

"People are advised to keep up to date with the latest forecasts in case parts of the watch will be upgraded to a full warning or further areas are added."

Heavy Rain Warning

Heavy rain may cause streams and rivers to rise rapidly. Surface flooding and slips are also possible and driving conditions may be hazardous.

Area: Coromandel Peninsula
Valid: 21 hours from 12am to 9pm Thursday
Forecast: Periods of heavy rain. Expect 100 to 150 mm of rain to accumulate. Peak rates of 15 to 25mm/h. Please note, east to northeast gales are also likely during the period, especially, in exposed places.

Area: Auckland north of Whangaparaoa, Great Barrier Island
Valid: 12 hours from 10pm Wednesday to 10am Thursday
Forecast: A period of heavy rain. Rainfall amounts may approach short-duration warning criteria. Please note, east to northeast gales are also likely during the period, especially in exposed places.

Area: Bay Of Plenty west of Te Puke, including the Kaimai Range
Valid: 24 hours from 3am Thursday to 3am Friday
Forecast: Periods of heavy rain. Rainfall amounts may approach warning criteria. Please note, east to northeast gales are also likely during the period, especially in exposed places.

Area: Gisborne north of Tolaga Bay
Valid: 30 hours from 12pm Thursday to 6pm Friday
Forecast: Periods of heavy rain. Rainfall amounts may approach warning criteria.

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