New Zealand weather: Wet but warm with temperatures close to May records

New Brighton beach might be the place to be Christchurch today - with temperatures expected to reach 25C. Photo / File

Rain's on the way, but don't bother with the woollies - May high temperature records could be nudged in some places today.MetService has issued heavy rain warnings for Westland, south of Otira, through to 3pm and in the ranges of Nelson, west of Motueka, to 6pm today. Heavy rain watches are also in place for the headwaters of Canterbury lakes and rivers, Westland from Otira north, Buller, the Tararua Range and Mt Taranaki today.

The high parked over New Zealand had been pushed to the east by a series of fronts that were bringing a lot of rain, MetService meteorologist Alwyn Bakker said.

"We're getting this wash of moisture travelling up the country. So most places are going to be seeing rain or showers, except generally the east."

But it will not be cold.

Eastern centres of the South Island were expecting highs 10C above normal for this time of year, Bakker said.

Christchurch and Kaikōura are forecast to reach 25C and Timaru 23C.

He didn't expect records to be broken, but highs may come close, especially in Kaikōura where the previous record for May was 25.8C, reached in 1999. Records in the town go back to 1991.

In Christchurch, where records date to 1863, the temperature reached 27C in 2002. Timaru's May record is 26C, also in 2002.

Other parts of the country would also be warm - Napier can expect 24C, about 6C above normal.

And it may also be windy for some today, with strong wind watches issued for Marlborough, Wellington and Wairarapa, south of Masterton.

In the top half of the North Island, temperatures are expected to remain in the low 20s until Wednesday, but that wasn't as far above normal as highs further south, Bakker said.

More noticeable in the north would be the mild overnight temperatures.

"In Whakatāne, for example, it'll be 16C overnight [tonight], instead of 8C."

The damp weather will continue through tomorrow and Tuesday, generally in western parts.

"It's that wet in the west, dry in the east deal - except that rain will be developing on the east coast of the South Island on Tuesday."

The wet weather will begin easing on Wednesday, except in Northland and Auckland, he said.