MetService is predicting up to six centimetres of rain an hour for parts of the upper North Island

A 19-hour heavy-rain warning applies for Northland from 3pm, with by severe thunderstorm and strong wind watches.

Watches and warnings kick in for Auckland and Coromandel Peninsula about 4am tomorrow.

Meteorologist John Law is urging locals to be vigilant of rising streams and rivers.

He says there are risks of strong rainfall bursts alongside the broad area of wet weather.

NZTA is advising extreme care on affected roads over the next 24 hours.