Far North severe thunderstorm warning: Flash flooding possible

At 04:15 pm, MetService weather radar detected severe thunderstorms near MANGAMUKA, BROADWOOD and THE MAUNGATANIWHA RANGE.

These severe thunderstorms are moving towards the east, and are expected to lie near MANGAMUKA and THE MAUNGATANIWHA RANGE at 04:45 pm and near MANGAMUKA… pic.twitter.com/Cm5vHNITSB

— MetService NZ (@MetService) August 12, 2026

A heavy rain watch has also been in force for eastern areas of the upper North Island since this morning, covering a 15-hour period of wet weather.

The watch, which came into effect at 10am today, covers northern and eastern Northland and Auckland north of Ōrewa, including Great Barrier Island, until 1am tomorrow.

Meteorologist Ashlee Parkes told the Herald a “quite complex system” is moving in from the west.

“There’s going to be scattered falls through most northern and western exposed areas as this front begins to push its way over,” she said.

In Northland and northern Auckland, the heaviest rain is expected from late morning through the afternoon, before easing in the evening.

Meanwhile, Tairāwhiti-Gisborne through to Wairarapa will start the day cloudy with light rain before fine spells in the afternoon.

As the front pushes south, Westland and Fiordland are also in for heavy falls.

Severe Weather Update – Heavy Rain Watches ⚠️

🟡🌧️ Northern and eastern parts of Northland, and Auckland north of Orewa including Great Barrier Island (10am Wed – 1am Thu)
🟡🌧️ The Westland District (2pm Wed – 6am Thu)

More info: https://t.co/VDYb51QBlL pic.twitter.com/1IlwNqJFMD

— MetService NZ (@MetService) August 11, 2026

“Our lovely Southern Alps across the South Island are going to do a pretty good job of blocking the worst of that rain and keep the heaviest stuff in the west,” Parkes said.

Marlborough south to Dunedin can expect a partly cloudy day with “light spots of rain on and off”, Parkes said.

A “quite significant northerly wind” will develop ahead of the front, becoming strong in exposed places, particularly around the eastern South Island coast.

By midnight, the front is expected to stretch from Auckland towards Westland and Fiordland.

Warm weather on the way

The system is also set to bring unusually warm conditions to some parts of the country.

Kaikōura is forecast to reach a toasty high of 18C tomorrow, with Parkes saying temperatures would be a “bit warmer than we would expect for this time of year”.

“We do often get these situations where, as these fronts cross the country, we get a northwesterly flow in behind, and they can be quite warm.”

The front will continue tracking southeast tomorrow, with a low risk of heavy rain in Coromandel and Bay of Plenty.

Wet weather is expected to linger across northern areas through tomorrow and into Friday as another feature draws “warm moist air from the subtropics” over New Zealand.