The future for Northland weather: Storm alerts are 'the new normal'

This year has already brought almost every possible weather extreme to Northland, with record rain hot on the heels of a drought, a cyclone and even a tornado. Are Northlanders experiencing a new normal? Is this a sign of things to come? Or just par for the course in a region that's always had its share of extremes?

First came the tornado that struck Mangawhai in the early hours of 26 January, tearing off roofs and leaving two people badly injured.

Then came the big dry, with some areas recording just 10 per cent of their normal rainfall. Drought was declared on 7 March.

Next, the heavens opened and Northland switched almost overnight from drought to flood. Kerikeri, Kaitāia and Whangārei all set new records for April rainfall.

Next, on 17 April, Cyclone Tam trashed Northland's power networks, leaving more than 24,000 households in the dark. It was a week before some homes had their power restored.

And it did not stop there, with slips triggered by more torrential rain closing State Highway 1 through Mangamuka Gorge twice in a matter of days.

So what's going on? Is this a new normal? Should Northlanders be preparing for ever more extreme weather?

MetService meteorologist Mmathapelo Makgabutlane said although drought was declared across Northland in early March, the big dry stretched back to the previous October.

"So that period of dry weather from last year spilled into this year, and the first three months of the year were particularly dry in Northland … But actually, interestingly, not long after that, in April, we saw quite a deluge of rain for many parts of Northland, in particular places like Whangārei as well as Kerikeri and other spots even saw their wettest April on record. So from extremely dry to very wet in quite a short space of time."

Kerikeri's April rainfall, 593mm, was almost four times the long-term average for the month of 151mm.

As for cyclones, however, Makgabutlane said the southwest Pacific experienced fewer than usual last season - with just one, Cyclone Tam, reaching New Zealand.

Just five reached the threshold of being given a name, half the long-term average.

Makgabutlane said climate modelling did not suggest more cyclones in future.

"But what is expected is for them to become more extreme, so more rain and stronger winds. It's the severity of those cyclones that is likely to change."

Droughts were also expected to become more severe, she said.

Modelling by Niwa and the Northland Regional Council suggested droughts would be more frequent in future, and last longer.

However, Makgabutlane said it was too soon to say if the extremes of the past six months were "the new normal".

"It has been quite tough on the ground in Northland, but it's probably still a bit too early to say if this is how it's going to be going forward. But it could be a hint of things to come in the future."

Far North Mayor Moko Tepania said of the six summers since he was first elected as a councillor, only one had been free of drought or water restrictions.

Those dry conditions also led to major wildfires, and late summer often brought damaging cyclones.

"In my first full year as mayor, we had Cyclone Gabrielle and ex-Tropical Cyclone Hale hit us. I think there were 13 or 14 significant weather events that year as well. So it was really a baptism of wind and rain as mayor," he said.

There had been little let-up since then.

"So it's been a pretty crazy three years as mayor, six years as an elected member."

Tepania said it was challenging for the Far North District Council to serve 75,000 people living in 40 settlements scattered across a vast area.

Many of those people struggled day-to-day just to get by.

"You put on top of that the extreme weather we've been experiencing and it all adds up, and brings monumental challenges to us. The biggest one that I've probably had to deal with or seen affect our people on the daily is, of course, our roading network," Tepania said.

"Our council has 2500km of local roads we have to look after. Cyclone Gabrielle caused over 140 slips across our network. We are still, to this day, working on 43 of those slips, and we will be spending something like $32.5 million over the next two years to still fix slip repairs that were caused by Cyclone Gabrielle two years ago."

Damage on that scale also had a huge impact on rates in a district where many people struggled to pay their bills.

It was fortunate that NZTA Waka Kotahi picked up a large share of the bill through regular funding assistance, reflecting the district's sprawling road network and affordability issues, topped up with emergency works funding.

Tepania said it sometimes felt like storms were lining up to have a go at the Far North.

Seeing Cyclone Tam bearing down in April brought back vivid memories of Cyclone Gabrielle.

"I was thinking, oh my goodness, we've only just got funding confirmation from NZTA to fix the remaining slips we've had since Cyclone Gabrielle, and we've finally got our tender panel up and running so that we can pump the work out to our contractors and get the work done a lot faster … and then you get another cyclone warning come through, and you see it tracking down, and you see the power going out across all of our towns, and you're waiting for the reports to come back. It's really frightening, to be honest."

Tepania believed Northland's recent weather extremes were part of a new normal.

He said he was proud of the work the council was doing to adapt to a changing climate, and helping communities prepare emergency response plans so they could better withstand future natural disasters.

He was also grateful to the Northland Regional Council for flood reduction schemes underway in places like Awanui and Moerewa, and to NZTA for a project at Turntable Hill which had ended years of flooding across State Highway near Moerewa.

Tepania said Far Northerners had made it through all the extremes nature had thrown at them in recent years because they were resilient, and they were prepared.

"Now it's the new normal that when we get a weather alert come through, or we tell our people we're at a yellow watch or an orange warning, people do take care. They check the tides, they make sure they know where their whānau are, and we manage to get through it each and every time, because it's the new norm," he said.

"I don't know what tomorrow looks like, I don't know what the rest of this winter looks like. So trying to be as prepared as possible, and for our people to be as prepared as possible, is very important."

* This is the first in a series exploring extreme weather in Northland, and what's being done to prepare for it and reduce its impact.

Sign up for Ngā Pitopito Kōrero, a daily newsletter curated by our editors and delivered straight to your inbox every weekday.