Drier than normal June forecast for lower North Island in Niwa winter seasonal outlook

Niwa's forecast temperature for the winter months, June to August.

Regions in the lower North Island can expect warmer afternoons as winter starts.

The National Institute of Water and Atmosphere Research’s seasonal climate outlook for winter (June, July, and August) says temperatures are likely to be above or near average for this time of year.

Niwa’s report states that an increase in high-pressure systems will cause cool, frosty mornings but warmer afternoons from the second half of June.

The chance of the lower North Island’s temperatures being above average and near average is about equal.

“A spell of warmer than average temperatures is expected during the first half of June followed by a return to more typical conditions in the second half of the month. Cold snaps, while expected occasionally through the season, will likely be brief,” the report said.

Niwa said the lower North Island was expected to have a drier June than normal, with rainfall totals estimated to have a 40 per cent chance of being near-normal and a 35 per cent chance of being below normal.

Chris Brandolino, principal scientist of forecasting and media with the Niwa National Climate Centre, said the statistics for Taranaki, Whanganui, Horowhenua, Manawatū and Kāpiti were similar.

“What this outlook does is identify themes and the theme here is that most of the country is in the same boat. In terms of the lower North Island specifically, rainfall is where it should be or slightly less over the coming three months.”

The air pressure is expected to be higher than normal near New Zealand, particularly in the North Island, most likely causing more westerly winds than normal.

In terms of temperature, Brandolino said southerly winds were expected to occur less frequently in winter than they did in autumn, which would influence temperature patterns.

“Since there is not expected to be as many southerly winds it won’t be as cold as usual. It’s looking highly unlikely that we will have a wet and cold winter.”