"Immensely humid" weather is about to hit the upper North Island with Auckland's temperatures forecast to be the same as Fiji this weekend.
Aucklanders have been sweltering in sticky weather for nearly a week but it's about to get worse.
WeatherWatch meteorologist Philip Duncan says tropical cyclone Dovi will push more humid air towards Auckland, while central New Zealand can expect heavy rain.
"The humidity is definitely about to increase. If you thought it was already muggy in the North Island, well this is going to pull down very humid air, Duncan said.
"The North Island on Saturday is peak tropics. The overnight low in Auckland on Saturday is 23 degrees with 90 percent humidity by the way, so is Nadi, Fiji. So it's going to be very humid on Saturday and a very tough night for sleeping."
Ducan said the humidity will continue into Sunday with drizzles and possible downpours expected. But things will finally start to cool down early next week.
"Auckland's overnight low is 23 degrees on Saturday night [but] could be only 16 degrees by Tuesday night."
Regardless, Auckland is in for an uncomfortable few days, he said.
Meanwhile the central areas should prepare for heavy rain with possible flooding, Duncan said.
"The bulk of the rain is coming through central New Zealand. There could be fooding anywhere from Taranaki, Whanganui, Manawatu, Kāpiti Coast and potentially Nelson, Motueka and maybe even over into Marlborough.
"So there is a lot of rain coming there but very little for the top [of the island] and very little for the bottom."
Canterbury can also expect rain as well as the West Coast.
The rain won't be welcome news for the West Coast with a state of emergency declared in Buller on Thursday.
It comes after the region was lashed by record rainfall overnight.