Your weather: Fine but sour conditions marked for South Island

It will be a fine day for most of the country with several centres across the North and South Island reaching into the low 20s.

It comes ahead of unseasonably wintry conditions marching north which will grip most the South Island at the weekend.

"It is looking quite pleasant over the North Island at the moment, there will be some showers in the north, in general, it will be pretty fine," MetService meteorologist Melissa Oosterwijk said.

"In Southland it is raining and that is spreading into Dunedin and North Otago. It will spread to Canterbury and Westland."

The rain was slow moving and the weather system would take most of the day before reaching Christchurch, she said.

Sea surface temperatures have been warming 🆙

Recent above average temps have caused the Tasman Sea to warm several degrees above average (🔴) pic.twitter.com/vHBx9aQQRm

— NIWA Weather (@NiwaWeather) November 15, 2018

Looking ahead to the weekend, on Saturday a front would move to Westland, bringing outbreaks of heavy rain.

There was moderate confidence that rainfall accumulations will meet warning criteria.

On Sunday the front would move north with cold southerlies forecast to spreading on to the southeast of the South Island.

There was low confidence of significant heavy rain in Southland and Otago, which would persist through to Monday.

From Monday to Tuesday, the rain would extend into Canterbury and southern Marlborough.

With the rain come strong and very cold southerlies - there is low confidence of severe south to southwest gales in Canterbury and southern Marlborough Monday and Tuesday - and snow could fall to 500 metres in Southland, 600 metres in Otago, and 800 metres in Canterbury, making for unseasonably wintry conditions, MetService said.

Your weather

Whangārei: Fine, but chance of a morning shower or two. Easterly breezes. High 21C Low 11C

Auckland: Fine, but chance afternoon or evening shower. Easterly breezes. High 22C Low 12C

Tauranga: Fine. Light winds and sea breezes. High 20C Low 12C

Whanganui: Morning cloud, then fine. Westerly breezes. High 21C Low 10C

Napier: Fine. Light winds and sea breezes. High 23C Low 13C

Wellington: Morning cloud, then fine with high cloud. Brisk northerlies. High 18C Low 13C

Christchurch: High cloud increasing. Rain developing at night. Easterlies developing in the afternoon. High 23C Low 10C

Dunedin: Rain developing this morning. Winds changing southeast around midday. High 17 Low 10C

Source: MetService