Source: Radio New Zealand
Unsplash / Daoudi Aissa
A formidable El Niño weather system is expected to arrive this winter, which could have a “significant” impact on rainfall across New Zealand.
Earth Sciences New Zealand said it was monitoring signs of a developing El Niño in the tropical Pacific Ocean for the past six months.
It said global climate models now showed a clear consensus for an El Niño event to arrive this winter, with a 60 percent probability that the event would be classified as ‘strong’ by spring.
There was also potential it could intensify further later in the year, it warned.
Earth Sciences New Zealand and MetService meteorologist Jon Tunster said that while La Niña had just ended, there were indications we would see a “rapid flip” to El Niño.
El Niño and La Niña are the two phases of the El Niño-Southern Oscillation (ENSO) – a natural climate cycle driven by ocean temperatures and atmospheric pressure across the tropical Pacific.
Supplied / Earth Sciences New Zealand
Tunster said El Niño’s forecast could result in a south-westerly flow over New Zealand.
“This could bring increased rainfall to Southland, parts of Otago, and western facing areas, primarily of the South Island, but reduced rainfall for much of the remainder of the country.
“Dryness could become an issue as spring approaches, for areas that see a reduction in their normal winter rainfall such as the east of both islands, or the upper North Island.”
However, Tunster said it was unlikely there would be a colder winter than usual for the country.
Flooding in Paeroa earlier this month. RNZ/ Nick Monro
We could see occasional cold snaps, lasting a few days at a time – except in inland parts of the South Island where the cold air can linger for longer periods, he said.
Earth Sciences NZ said dramatic impacts on globally important large-scale weather systems looked likely, including the Indian monsoon and the North Pacific storm track.
“Given the projected strength of this event, it will be very surprising if New Zealand doesn’t feel some impacts,” Tunster said.
“However, surprises are always possible.”
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– Published by EveningReport.nz and AsiaPacificReport.nz, see: MIL OSI in partnership with Radio New Zealand
