After a weekend of thunderstorms and heavy rain, forecasters say warm and humid weather is set to hit most of the country - but not all.
Auckland is not expected to drop below 16C at night for the next week at least.
"[It's] a sign of some sticky nights to come," MetService says.
On Wednesday, much of the country will be warmer than average as warm winds move in.
Auckland's expected to reach 25C, Taupō 26C, Dunedin 20C, and Wellington and Christchurch both 22C.
But it's not all good news. A slow trough moving across New Zealand this week means some parts of the country could see some rain.
"This system is weaker and the weather is not expected to be as severe," MetService meteorologist Tom Adams said.
A heavy rain watch is in place for Otago, the south Canterbury High Country, and southern parts of Westland. The heavy rain could cause issues in areas still waterlogged from the weekend's bad weather, MetService warns.
On Wednesday, the North Island will see plenty of sunshine, while cloud will blanket most of the South Island. On Thursday, the lower half of the South Island may have isolated heavy showers and possible thunderstorms.
Whangarei's expected to hit 28C, Auckland 26C, Hastings 28C, Christchurch 27C, and Dunedin 21C on Thursday.
The trough is expected to move away on Sunday, with more settled weather taking hold - for a few days at least.