New Zealand weather: Summer in spring for some, before rain and showers arrive

Spring has turned to summer around the country this weekend, thanks to a high pressure system over the north and warm nor'wester winds blowing across parts of the south.

Aucklanders were out enjoying the sunshine yesterday after avoiding any possible lockdown with the latest Covid case genomically linked to the Defence Force cluster.

It was as if summer had already arrived at Mission Bay with plenty of kids out and about in the water - and the sand.

The summery vibes continue today as temperatures in most main centres will top 20C, with Christchurch, Blenheim and Timaru expecting a summery 25C and Tauranga 24C.

Upper North Island centres can expect highs in the low 20s - Auckland and Hamilton should reach 22C, Rotorua 21C and Napier 23C.

Temperatures in the North Island were about normal for the time of year, but above average for parts of the South Island thanks to the nor'wester, MetService meteorologist Kyle Lee said.

"In the east we're talking 4C to 7C above average."

It's a cooler day in western and southern parts of the North Island - Wellington will be fine but with a high of 18C and New Plymouth, also fine, 19C.

Most places will be dry, with the exception some parts of the deep south, Lee said.

"It's pretty benign weather today. There's a bit of high pressure keeping much of the country pretty fine."

Scattered showers may spoil the party in Otago, Southland and parts of Westland and a heavy rainfall warning has been issued for Fiordland - up to 150mm of rain is expected before 9pm tonight.

Meanwhile, Sunday's sunshine across much of the country will give way for some to a damp start to the working week.

North Islanders can expect showers to spread across much of the island, from Northland to Wellington, and from Taranaki towards eastern areas.

It'll be mild in Auckland, with a high of 22C but showers will develop from afternoon, with a similar story in Hamilton.

Brief evening rain is expected in Wellington tomorrow, with a high of 18C.

In the South Island rain and showers are expected for many places during the day, before clearing in the evening.