Most of the country will enjoy a bit of sun before Friday marks the start of more wet weather to finish off the year.
MetService meteorologist John Law said rain coming in from the Tasman Sea was to blame.
"As we head towards the end of the year we have got a dry couple of days coming up towards us, however things are set to change as we head into Friday as more wet weather moves back in from the Tasman Sea," he said.
Most parts of the South Island and also Wellington will enjoy a day of sunshine on Thursday before the rain sets in, Law said.
For other parts of the North Island though, there will be a fair bit of cloud before more wet weather on Friday.
"Wetter weather pushes back in from the west, some heavy rainfall and some more blustery conditions," Law said.
"There are already some severe weather watches in place around those western parts of the country on the South Island and also toward places like Mount Taranaki."
MetService has issued heavy rain warnings for Taranaki, Nelson, northwest of Motueka and the ranges of Westland, south of Otira, starting from Friday.
Westland, in particular was forecasted to receive up 160mm of rain. There would be peak rates of up to 30mm per hour on Friday with another burst of heavy rain expected overnight Saturday and New Year's Eve morning.
Meanwhile, there were heavy rain watches in place for the ranges of the eastern Bay of Plenty, Tongariro National Park and the Kaimanawa Mountains from Friday until Saturday morning.
Richmond and Bryant ranges, including the Rai Valley, Buller, west of Reefton will also get their share of the wet weather on Friday with periods of heavy rain.
Fiordland, north of Doubtful Sound, has a heavy rain watch for a full 24 hours from 4am Friday to 4am Saturday, with another burst of wet weather in the evening and early on New Year's eve.
For other parts of New Year's Eve, MetService was forecasting a few showers for the North Island, turning to rain for a time.
The South Island was expected to be hit with possible heavy falls in the north and west, with showers spreading north elsewhere.