Torrential rain and thunderstorms overnight in Auckland had Fire and Emergency responding to 71 callouts for flooded or weather-damaged homes.

MetService said up to 100mm of rain fell in places between 9pm and 11pm on Monday night.

Homes were flooded in the east and south of Auckland, including water pouring through ceilings, Fire and Emergency said.

Fire and Emergency said it received 71 callouts, mostlu in Kohimarama and St Heliers.

It comes as a 'Tasman Sea Special' is on its way, bringing stormy weather to parts of the North Island.

A string of heavy rain watches and warnings for the next few days have been issued by MetService.

The low-pressure system will also bring strong winds.

A severe thunderstorm watch is in place for Bay of Plenty and Rotorua this morning till 10am.

That brings the possibility of a coastal tornado, and MetService is also warning of torrential downpours of more than 40 mm/h, especially in coastal areas.

There is a heavy rain warning in place for Hawke's Bay until 6pm Wednesday.

On Monday night 80.6mm rain was recorded in Leigh, north of Warkworth, and overnight 63.0mm was recorded in Whangaparaoa.

MetService meteorologist Josh Griffin said severe or heavy rain warnings were usually based on 100mm of rainfall over 12 to 24 hours. "We were seeing that amount in about two or three hours. So we were seeing some torrential rainfall."

MetService said the rain had mostly moved on from Auckland.

"A complex low-pressure system - a 'Tasman Sea Special' - is currently approaching Aotearoa/New Zealand, with an extended band of rain already affecting parts of Northland," MetService meteorologist Dom Barry said.

"As the low moves southeastwards across the motu, we can expect areas such as Marlborough and Northern Canterbury to encounter some wet weather from Tuesday, with the rain mainly remaining in the eastern North Island."

Meanwhile, the west of the South Island will be the place to be for some sunshine.

This story was originally published by RNZ