It's shaping up to be a dry New Year's Eve but you'll need to wrap up warm if you're planning to ring in the New Year outdoors.

The top of the country looks set to be the warmest place to farewell 2020, with a high of 25C and a low of 14C predicted for Whangārei - although there could be a few showers in the afternoon.

Auckland is not far behind, with a high of 24C and a low of 15C.

From Wellington up the west coast and through the central North Island there was expected to enjoy fine weather all day, although the temperatures were likely to sit slightly lower at about 22C.

Around the country the forecast for tomorrow is for fine weather for most parts, however the West Coast may see some patchy rain later in the day while inland parts of Southland, Otago and South Canterbury could see downpours developing and turning to rain overnight, according to Weatherwatch.

It could be a wet night for those heading to Rhythm and Alps, with rain predicted to set in tomorrow evening around Wanaka.

In the North Island, the day might start with a few patches of drizzle around Gisborne and coastal Hawke's Bay but it should clear by evening.

Most of the country can expect normal summer temperatures during the day, with the bottom of the South Island a few degrees hotter than usual. In the North, coastal Wairarapa, Hawke's Bay and Gisborne will be a few degrees cooler than normal.

As for the evening, the North Island is likely to be slightly cooler than usual while the South may remain slightly warmer.

MetService meteorologist Andy Best said the top of the North Island was likely to see temperatures of 20C to 24C during the day with the rest of the North Island sitting around 20C to 22C. Overnight lows were expected to be 10C to 12C in most places.

As for the South Island, Alexandra and Wanaka could hit 25C or 26C but the rest of the island was likely to sit around 20C to 21C. Overnight the temperature for most parts would be in the low teens, he said.

New Year's Day looked like it could be a bit damper around the country, Best said.

The day was predicted to start with showers in Auckland and Northland which moved down to the Coromandel and Bay of Plenty by afternoon.

In the lower half of the Southern Island heavy rain was likely to stick around for most of the day.

The New Year's Eve forecast

Whangārei: Fine, but chance of a shower in the afternoon or evening. High 25 degrees, low 14 degrees.

Auckland: Mainly fine. Light winds. High 24C, low 15C.

Tauranga: Fine. Light winds and sea breezes. High 23C, low 14C.

Napier: Cloudy periods. A few showers, clearing during the morning. Southerlies dying out in the afternoon. High 21C, low 12C.

New Plymouth: Fine. Light winds. High 21C, low 12C.

Wellington: Morning cloud, then fine. Southerly breezes. High 20C, low 13C.

Nelson: Some morning cloud, then fine. Cloud returning in the evening. Light winds. High 20C, low 13C.

Christchurch: A mostly cloudy day but some afternoon fine breaks. Fresh northeasterlies. High 19C, low 11C.

Queenstown: Mostly cloudy. A few showers from afternoon, some possibly heavy. Light winds. High 22C, low 13C.

Dunedin: A mostly cloudy day with a few showers from afternoon. Northeasterlies. High 20C, low 13C.