The recent theme of warm and mostly dry weather is set to continue until the New Year, according to MetService.

Photo: file.

This news will no doubt be welcomed by holiday-makers, but may not be what farmers in already parched areas want to hear. It's been mostly sunny and warm across the country, as a narrow ridge of high pressure remains over central New Zealand.

MetService meteorologist Peter Little says the highest temperatures are expected about northern and inland parts of the North Island, also inland parts of the South Island, where temperatures could reach 30-degrees in some places.

This daytime heat, combined with instability in the atmosphere, may produce a few showers over the South Island, with the possibility of a thunderstorm or two about inland Otago. The ridge of high pressure slides eastwards on Wednesday, allowing a front to move northwards over southern and central NZ, followed by cooler southwesterlies.

Meanwhile, another front moves onto the west of the North Island.

"Despite the high losing its grip on the country, these frontal features are weak, so although most places will see more cloud than in recent days, only scattered showers are likely,” says Peter. A new ridge of high pressure builds over southern and central NZ on New Year's Eve, whilst a northeasterly flow develops further north.

"For much of the country fine and warm weather returns to welcome in the New Year, although isolated showers are expected about northern and inland parts of the North Island,” adds Peter. With the New Year comes the likelihood of a period of rain for northern and central New Zealand, as a strong, moist northeasterly flow drags sub-tropical air southwards.

"Heavy falls are possible, especially in the north on Saturday, so people are advised to check the forecast and plan accordingly,” says Peter.

MetService says a ridge of high pressure is expected to spread over the South Island on Thursday, while a moist easterly flow becomes established about the upper North Island.

A subtropical low is expected to move south towards the far north of NZ during the weekend, however, the track and depth of this low is still uncertain.

Rain is forecast to spread over the upper North Island on Friday, then through central areas during Saturday. There is a high confidence of heavy rain about Northland, northern Auckland and Coromandel Peninsula from Friday to Saturday.

In addition, there is a moderate confidence of heavy rain about the remainder of Auckland, eastern Waikato, Bay of Plenty and northern Gisborne from Saturday to Sunday, with a low risk about the remainder of Waikato, Waitomo and Taupo.

Easterlies are forecast to strengthen about northern areas during Saturday, with a low risk of northeasterlies reaching severe gale for a time about northern parts of Northland.

On Sunday, a cold front spreads north over the country, with outbreaks of rain or showers spreading over eastern parts of the South Island and the remainder of the North Island before slowly clearing on Monday.

Keep up to date with the latest forecasts and any watches/warnings at metservice.com or on mobile devices at m.metservice.com