A severe thunderstorm warning across most of the North Island has been issued by MetService as rain pelts down on Wednesday afternoon.
The warning is in effect until 7pm for people in Northland, Auckland, Waikato, Waitomo, Taumarunui and Taranaki.
The thunderstorms are slow-moving, which produces patches of heavy downpours, MetService says.
Mostly rainfall is 15mm to 25mm, but there some areas that could be hit by hail, and up to 40mm of rain.
Heavy rain has caused flash flooding in Papakura on Wednesday afternoon (Tim Raethel / Newshub.)
(Tim Raethel / Newshub.)
Drivers are being warned to watch out for flash-flooding, rising streams, and landslips, and to drive to the conditions.
Further thunderstorms could hit again tomorrow, MetService reports.
In Northland, a swollen creek has trapped a vehicle at Waipu Gorge Road. The fire service says it's waiting for the water level to go down before helping the occupants across a ford.
The fire service also were also called to the ANZ building in Manurewa, where a ceiling had collapsed after heavy downpours and a burst water pipe.