‘Formidable’ El Niño weather system to hit NZ this winter - but what does that mean? | Stuff.co.nz

Added: 2026-05-06

[00:00:00]What's been described as a formidable El Nino weather system is set to hit New Zealand this winter, which could have a significant impact on rainfall across the country.

[00:00:10]Earth Sciences New Zealand has been monitoring the weather pattern for the past 6 months, releasing its findings today. The chief scientist Chris Brandolino joins me now. Kyota Chris, so what kind of weather might we be in for?

[00:00:23]Okay, Sam. So El Nino historically brings during the winter season and beyond winds coming more from the southwest and the west. So a couple things to take away from that. One, for a good chunk of the country not named the west of the South Island, you tend to have dryness. In fact, we'll be issuing our updated 3-month outlook tomorrow.

[00:00:43]Um and just a bit of a sneak peek, it looks like that theme for a risk of dryness will be a theme for much of the country bar the west of the South Island. Um and that sort of air flow, Samantha, southwest winds, not exactly a warm wind direction. So the odds for getting extended spells of warmer than usual temperatures are going to be reduced. Yeah, so what I'm hearing there is that some parts are going to get increased rain. Other parts of the country are set for a dry winter. What are the repercussions of all that?

[00:01:16]Yeah, winter is a very important time of year for rainfall. I know a lot of us are probably um wouldn't mind a lack of rainfall in winter. You know, no doom and gloom, right? But winter is important from an agricultural perspective. It's what we call ground water recharge. Think of the ground like a battery.

[00:01:32]During the spring, during the summer, when we're growing vegetables in our gardens, a lot of that water leaves the ground from the vegetables of the gardens or from the sun.

[00:01:40]Now it's the time of year we want to recharge that ground with water. And if we don't do that adequately, we could be walking into the new growing season um behind the eight ball, so to speak.

[00:01:50]So I, you know, lower than usual ground water, which would not be a good thing.

[00:01:54]Okay, so your global climate model has highlighted how much the Pacific Ocean temperature has actually warmed since January, uh I believe causing the El Nino event.

[00:02:04]Uh how much does that concern you?

[00:02:07]Yeah, so during the past several months, we've had La Nina, which is the opposite of El Nino. And what we're looking at here are ocean temperature anomalies.

[00:02:16]That's just a big fancy word for difference from average. Where is it unusually cool? Where is it unusually warm in terms of the ocean? And that orange and red that we're seeing emerge off the South American coast, that is an indication that of El Nino emerging.

[00:02:29]Hasn't happened yet. So El Nino is not quite here yet, but we're expecting over the next couple of months that will happen. And the fact that this is happening so quickly, and the fact that these ocean temperatures near the Galapagos Islands, out near South America, they're going to become so unusually warm. This could be a strong to even a very strong El Nino, what some people call a super El Nino. So the last time that happened, I think 2015, 2016, 1997, 1998, also '82 and '83. And there was a lot of dryness around during those El Nino events. So another reason why we're sort of, you know, we're very mindful in monitoring how this will evolve over the coming months. Okay, we'll leave it there. Thank you so much uh for your time today. Earth Sciences chief scientist Chris Brandolino. Tina Kwi, thanks so much.