For many parts of the country, it might feel like summer has yet to arrive - and NIWA's latest climate outlook is still predicting heavy rain in mid-to-late January.
The wet weather is due to warmer ocean temperatures driving up the heat, humidity and moisture - so this El Niño isn't behaving as expected.
"We may see some big rainfall events for the Upper South Island and North Island for that second half of January," said NIWA's principal scientist of forecasting, Chris Brandolino.
There's more of the hot and humid coming too, with marine heatwaves to blame in the north.
"The ocean temperatures around New Zealand, and even regionally up to the coral sea, have gone unusually warm," Brandolino told Newshub.
"That's important because when our air flow comes from the north and north-west, that air flow goes over unusually warmer oceans which can mean higher humidity, warmer temperatures and more moisture."
However, come February, Aotearoa should finally see some long periods of fine weather.
"So perhaps more sustained, more prolonged dry periods as we work our way into February and March. It's only early January, we have plenty of summer to go," he added.
NIWA's latest climate outlook indicates the entire country could see above-average temperatures from January to March.
Most of the country is in for near-average rainfall, but places like the Bay of Plenty, Hawke's Bay, Tairāwhiti, Auckland and Northland could experience some heavy downpours in late January, said Brandolino.
This means droughts and water restrictions can't be ruled out.
"Let's keep our guard up, as we could still see dryness emerge in the back half of summer and into autumn," Brandolino said.
A climate outlook is very different to a forecast and things can change, he stressed.
"The purpose of an outlook is not to give you a weather forecast, the purpose is to identify themes to understand what will define the next three months."
