MetService has warned such severe storms can produce marble-sized hail and rain, which can cause surface or flash flooding, especially in low-lying areas.
For the remainder of Northland and Auckland, there is a moderate risk of thunderstorms in the afternoon and evening.
“The nature of this type of shower activity is it’s a big area that can be affected, but they pop up in very localised places,” said Pawley.
Despite the downpours, temperatures of 25C today and 24C tomorrow are forecast for Auckland.
The bad weather is expected to hang around tomorrow with thunderstorms possible across the upper North Island.
Tomorrow afternoon there is a moderate risk of thunderstorms with heavy rain affecting Gisborne, Bay of Plenty, north Taupō, eastern and northern Waikato, Coromandel Peninsula, Auckland and Northland.
For inland Northland, the far east of Waikato, Rotorua and inland Bay of Plenty west of about Kawerau, there is a 10-30% risk of severe thunderstorms with localised downpours of 25-40mm/h, according to MetService.
Despite bad weather in the north, a sunny Saturday is in store for most of the country today.
MetService said the middle part of the country will have high temperatures and sunny weather, with Gisborne predicted to peak at 28C.
In Hawke’s Bay, temperatures above 25C are forecast around the region with some places reaching 30C early next week.
On Monday, the western South Island is forecast to get heavy rain with a heavy rain watch in place from 9pm on Sunday to noon the following day.
The same watch is in place for the ranges of the Westland District from 3am-3pm on Monday.
