Fine weather is expected for the majority of the country, with some isolated showers in Auckland possible in the afternoon, MetService says.
Meteorologist John Law said a high pressure was in charge on Tuesday, bringing dry conditions and warm temperatures.
Overnight, Law said the North Island experienced high and humid temperatures, with a low of 17C.
Temperatures in the South Island were "much more comfortable".
But Law said "Tuesday is panning out to be a pretty decent day" for many places across the motu.
There could be cloud across northern parts of the country from Northland, Auckland, across Coromandel and to Bay of Plenty.
The clouds could bring some isolated showers to Auckland in the afternoon, Law said.
Further south, dry and fine weather was expected "across the board" but it would not be as warm as it had been.
Christchurch could reach 21C in the afternoon and Mount Cook village could see 25C, he said.
Auckland could also see 25C and Wellington's high was 21C.
On Monday, MetService said rain could spoil some people's Christmas plans, with wet weather possible for several places next Monday.
MetService meteorologist Lewis Ferris said there was still time for the weather to change, and it was a bit tricky to currently predict.
"We might not just see rain on the west coast of the South Island, it might even be spreading up into the North Island, but the typical hot spots, the eastern parts of the South Island, and the North Island, up in the Bay of Plenty, do look like the most likely places to have settled weather next Monday, but we are still a wee way out."
Ferris said certainty of the weather would become clearer as the week went on.
He suggested people wait a few more days before planning to hold their Christmas Day celebrations indoors or outdoors.