Whangarei, Auckland, Tauranga and Hamilton are all set to hit 23C today, with just the odd isolated shower from Coromandel to Northland, and similar weather is forecast through the weekend.
It will be sunny but slightly cooler in southern areas. New Plymouth has a high of 20C forecast, and Wellington 19C with strengthening northerlies.
The South Island will feel most of the weather today.
A front begins to arrive in the lower parts this morning, with a period of heavy rain.
The front will move north into Otago in the afternoon, and bring scattered rain to Canterbury by the evening.
Temperatures will drop in the east as warm northwesterlies make way for a cold southerly.
Christchurch goes from a high of 24C today to 16C tomorrow, and Dunedin 20C to 16C.
On the West Coast, heavy rain will set in through the day, reaching north Westland and Buller by the evening. A heavy-rain watch is in place for Fiordland and Westland from this afternoon into the evening, with possible thunderstorms.
Temperatures are forecast to be in the late teens there today and through the weekend.
MetService meteorologist Kyle Lee said the North Island was looking mainly fine again on Saturday, with a few showers expected from the front in southern and eastern areas.
The South Island will be a little more wet, as a weak front affects the west and south.
That weak cold front will bring some isolated showers to parts of the southern North Island on Saturday.
"Wellington will see a few showers on Saturday, but that is expected to clear in the afternoon, so just a heads up if you are heading to Homegrown early to remember a raincoat," said Lee, refering to the music festival in the capital that takes place this weekend.
After the front passes on Saturday, the weather will improve across the country before another cold front is expected to arrive in the South Island on Sunday.
"This cold front will bring some strong winds and colder temperatures with snow about the higher ground, potentially lowering even further for a time on Tuesday," Lee said.
"The blustery cold start to the week will be a bit of a change to the relatively mild Autumn we've had so far."
Today's weather
• Whangarei
Partly cloudy, chance of a shower. Southerly breezes. 23C high, 14C overnight.
• Auckland
Partly cloudy, the odd shower north of the city. Light winds. 23C high, 15C overnight.
• Hamilton
Fine apart from morning cloud or fog. Westerly breezes developing afternoon. 23C high,
10C overnight.
• Tauranga
Mainly fine, some morning cloud. Light winds. 23C high, 13C overnight.
• New Plymouth
Fine apart from morning and evening cloud. Southwesterlies. 20C high, 14C overnight.
• Napier
Fine apart from some morning cloud. Light winds. 25C high, 12C overnight.
• Wellington
Fine. Northwesterlies strengthening. 19C high, 14C overnight.
• Nelson
Fine, southwesterlies dying out in the morning. 22C high, 13C overnight.
• Christchurch
Increasing high cloud, rain at night. Northeast tending gusty northwest in the afternoon. Late southerly. 24C high, 11C overnight.
• Dunedin
Afternoon rain, then a few evening showers. Gusty northwest changing southerly.
