This warning comes from National Institute of Water and Atmospheric Research (Niwa) meteorologist Ben Noll, who says El Niño conditions will rapidly shift weather patterns in the coming weeks and months.
He says the first records could fall as early as late September.
“As we look to the back 10 days of the month, we’re going to have air masses coming across the Tasman from the deserts of Australia,” says Noll.
“When those air masses reach New Zealand and the air parcels descend the Southern Alps into the Canterbury region, as well as Otago, Marlborough, Hawke’s Bay, Gisborne and Wairapa, they warm up and dry out.”
That hot, dry air carries the potential of having a sharp impact on the weather we experience on the ground.
“We could be looking at 25C temperatures, maybe even higher, during the last week of September. If we look back, New Zealand’s national temperature record for the month of September was 28C.
"If we reach that in the final week of the month, it will put us up there with the very warmest September days that New Zealand has experienced.”
This will only mark the start of what could be a summer very different from the recent ones the country has experienced.
“The last couple of summers, there’s been a lack of 35C-plus temperatures, but I think that streak is going to end,” says Noll.
“This summer, we could be reaching 36, 37, 38 or maybe even 39C later in 2023 and early 2024 when these hot and dry air masses transit the Tasman Sea from Australia.”
Those rejoicing about the prospect of a hot, dry summer might want to pop the cork back into the Champagne, however.
The prospect of these conditions will pose a range of risks Aotearoa has not seen for a few years.
“The El Niño we’ve got building is among the strongest we’ve seen in the last 80-plus years,” says Noll.
New Zealand previously had strong El Niño conditions in 2015-16, 1997-8, 1982-3 and 1972-3 – and the consequences were felt around the country.
“New Zealand had historically bad, and very costly, droughts in some of those years,” says Noll.
“From an agriculture perspective, even though it’s been very wet and your paddocks may still be damp, the combination of drier weather and winds could see soil moisture levels drying out pretty rapidly.”
