Cold snap set to hit much of New Zealand

The southerly change will bring a sharp fall in temperatures for much of the country. Photo / iStock

The warm weather of the past few days takes a break this week, as a cold snap envelops the country - but Aucklanders will be spared the worst.

The southerly change will bring a sharp fall in temperatures and even the outside chance of a frost in rural Wairarapa on Thursday morning.

It has already reached Stewart Island and Invercargill this evening and tomorrow makes itself known to mainlanders.

Christchurch's daily highs are marooned on 14 or 15C for the next couple of days and those awake early will feel a chilly 5 or 6C dawn nipping at their feet.

It's even colder in Alexandra, which will be about 3C tomorrow morning, MetService meteorologist Emma Blades said.

"It's really, really cold there. They are only going to get to 15 or 16C."

Socks are also a must in Invercargill, which will reach 12 or 13C tomorrow but drop to only 2 or 3C by Thursday morning.

The North Island will really feel the cold on Thursday as the hot temperatures that normally bring a bede of sweat to those on the east coast disappear.

Napier and Gisborne will only reach about 15C, and will start the day with 5 or 6C.

Wellington is forecast to reach 13 or 14C, but a southerly wind could pack a greater punch.

Up north, Auckland will be spared the worst of the cold snap with temperatures only a couple of degrees down, into the high teens.

Ms Blades said despite the temperature drop, snow would only hit mountain areas, with falls forecast this week 1000 metres above sea level.

Warmer weather should take over again on Friday.

Forecast for the main centres:

Auckland:
Tomorrow: Cloudy periods and late showers in the west, 19C
Thursday: Morning rain and then showers, 18C

Wellington:
Tomorrow: Rain, with a strong southerly change, 16C
Thursday: Rain eases, strong southerly 13C

Christchurch:
Tomorrow: Rain, with a cold southerly, 15C
Thursday: Showers clearing and southerlies easing, 14C