Severe Weather Warnings Blanketed North Island as Torrential Downpours and Thunderstorms Threaten Flooding

Meteorologists issued severe thunderstorm and heavy rain warnings across roughly half of the North Island on Monday and Tuesday as torrential downpours threatened flash flooding and hazardous driving conditions.

MetService placed watches and warnings over Northland, Auckland, Great Barrier Island, Coromandel, Waikato, Waitomo, Taupo, Taranaki, Taumarunui, Tongariro National Park, and parts of the Bay of Plenty and Gisborne.

The incoming weather follows severe storms on Saturday that produced more than 5000 lightning strikes, damaged vehicles with large hailstones in the Waitakere Ranges, and disrupted flights and sports matches.

The persistent downpours pose ongoing risks to low-lying areas, rivers, and narrow valleys while bringing muggy, subtropical temperatures that will linger across the region before pushing further south.

“People across the upper North Island are already feeling the effects, with periods of heavy rain and thunderstorms,” said MetService.

Forecasters said rainfall intensities could reach 25 to 40 millimeters per hour in affected areas, creating dangerous conditions for motorists.

“Rainfall of this intensity can cause surface and/or flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips,” MetService said.

The agency also warned that driving conditions would become hazardous due to surface flooding and poor visibility during the heaviest downpours.

The weather system is driven by a low-pressure system whirling over the Tasman Sea that is drawing warm, moisture-laden air from the tropics down toward New Zealand.

Paris Marshall, a meteorologist, said the system had been collecting moisture from the ocean before heading toward the country.

“It’s just been whirling away for a while, collecting all this moisture from the ocean,” Marshall said.

John Law, another MetService meteorologist, said warm and humid conditions provided ideal environments for the intense rain showers and lightning bursts to form.

The NZ Herald reported that Whakatane and Whitianga were forecast to reach sweltering overnight lows of 17 degrees Celsius.

RNZ reported that radar detected severe thunderstorms near Te Puke and Paengaroa late Monday night, moving south toward Rotorua and surrounding lakes.

1News reported that an orange heavy rain warning was issued for eastern areas of the North Island, including Gisborne north of Tokomaru Bay.

Meteorologists expect the system to eventually push off from the North Island by Wednesday, bringing wetter and muggier conditions to parts of the South Island.