El Nino’s ‘turbulent’ impact will be felt in Whanganui this winter and spring

The climate driver El Nino will bring more "windy, turbulent" weather to Whanganui, Niwa says. Photo / Bevan Conley

Weather in Whanganui is set to get a shake-up over the coming months, with El Nino bringing noticeable changes.

El Nino, a climate driver at the opposite end of the scale to La Nina, is emerging in the tropical Pacific Ocean near the equator, close to the Galapagos Islands off South America and north of Tahiti.

Niwa (National Institute of Water and Atmospheric Research) forecaster Chris Brandolino said the ocean had become unusually warm there and when that happened, particularly in the winter, New Zealand tended to get more winds from the southwest.

“People will probably notice this over the coming three months. Winter and early spring can be windy, turbulent periods by nature, but this will be even more than usual.

“Whanganui on the West Coast may find there’s an increase of more rainy days and noticeable wind.”

Warmer sea and air temperatures

Brandolino said ocean temperatures in the Tasman Sea were one degree above average for this time of year.

“It’s not warm enough to go for a dip without a wet suit but it’s warmer than it typically is.

“That trend is going to help keep air temperatures warmer because as an island nation, often times ocean and air temperatures are closely related.

“I think in the next three months there are equal chances for average or warmer-than- average temperatures.”

Winter may feel colder overall

“We’re coming off of the back of three record-breaking warm winters in the last few years, so even if we have an average winter in terms of warmth, it might feel a lot colder because it’s been so warm previously.”

Brandolino said there will be periods of cooler weather, but the cold snaps may not be as frequent or as sharp.

“In the past several months the winds have been favouring the northeast, and for Whanganui’s neck of the woods that tends to warm things up and gives more sunshine, but we may see less of that.

“It may mean less sunny days than we’ve gotten used to over the past several months and few years.

“There may be more windy days than usual.”

Normal rainfall and less chance of extreme rain events

“Over the next few months, there are equal chances for normal or below-normal rainfall,” Brandolino said.

“It’s unlikely we will have those big rainfall events where there is a huge amount of rain in a day or two; we certainly don’t want to say there’s no chance, but because we are shifting towards a different climate driver those sorts of events become less likely.”

Eva de Jong is a reporter for the Whanganui Chronicle covering health stories and general news. She began as a reporter in 2023.