Get ready to strip off your winter layers as a stream of humid air creeps over the country today.
The last days of spring are forecast to be hot and muggy as subtropical air spills southwards towards New Zealand from today until Saturday, forecasters say.
And some parts of the east are heading for 30C or more.
Cantabrians will be making a beeline for the beaches as temperatures soar towards 30C today - already hitting 25C by 11am - and blustery northwesterly winds are possible in Southland, inland Otago and Canterbury overnight.
WeatherWatch head analyst Philip Duncan said other centres in the east of the country would see temperatures between 26C and 32C.
It was a humid heat in the upper North Island and Auckland was already clocking 19C before 8am.
It had 90 percent humidity before 10.30am, he said.
"For those working outside it will feel more like the mid 20s, then mid to late 20s into the afternoon. This doesn't apply to Auckland only, but actually for many North Island regions under similar conditions today."
A slow-moving front was expected to appear over the upper North Island on Saturday, bringing rain or showers, while Sunday would be clear and dry for most areas, he said.
"New Zealand will be mostly dry today, but the hotter [northwest winds] are going to strengthen and then head into the lower North Island on Friday where Wellington should receive gales, and a band of rain is moving up the western coastline," Mr Duncan said.
Today could be the first of many hot days as long-term forecasts indicate an El Nino summer, possibly bad news for farmers but good news for sun-worshippers.
MetService meteorologist Claire Flynn said parts of the east coast in the South Island would get towards 30C today.
Canterbury forecast was for 28C and inland areas could get even hotter, with strong winds driving the warm weather, she said.
"As the wind comes over the ranges and goes over the other side, it dries out and warms up a lot, and brings these really high temperatures.
"While it's nice and warm, it might not be a good day for a picnic," Ms Flynn said.
MetService has issued a warning for gales over the next 24 hours, gusting over 130kmh, possibly topping 160kmh in the eastern lee of the Southern Alps.
