Warmer weather's on the way for the South at the weekend, following scorching temperatures in Australia.
A heatwave on Saturday in Sydney was expected to drift over the Tasman Sea to the South Island on Sunday, then the North Island on Monday.
Temperatures were predicted to soar as high as 40degC through inland New South Wales and Sydney may hit 36degC.
Government forecaster the Bureau of Meteorology reported it would be the first time in history the state had reached 40degC in the month of September.
The heatwave should lose about 10degC by the time it reached New Zealand, making for balmy temperatures in the late 20degCs and early 30degCs, WeatherWatch head analyst Philip Duncan said today.
"The air loses a lot of warmth as it leaves hot inland Australia and crosses over the cooler waters of the Tasman Sea. It then warms back up again a bit as it crosses over the ranges of New Zealand.
"If New South Wales is heading to 36 to 40 degrees this weekend, it's fair to suggest that the east of the North Island will climb into the mid to late 20Cs.
"I don't expect 30 degrees here, but, I also can't rule it out as the ingredients are there under perfect conditions to climb that high."
Extra cloud in the South Island may reduce the heat though.Â
Southland, Otago, Canterbury and Marlborough were all expected to reach the 20degC mark on Sunday, with some making the mid-20degCs if conditions were sunny and windy from the north to northwest during the afternoon.
"We may see some areas go a bit higher if the sun is out and windflow is coming off the hills at the right angle to create additional heat," Mr Duncan said.
MetService was forecasting Alexandra to be the pick of the bunch in Otago and fine with a high of 21degC; Dunedin was set to be sunny and 19degC; Queenstown fine and 18degC; Oamaru sunny and 17degC and Invercargill and Gore both sunny and 20degC.
WeatherWatch suggested inland Hawke's Bay may reach the mid 20degCs on Monday, but the nor'wester would heat up some areas even higher.
New Zealand's complicated geography means not all will feel the heat - those along the Tasman Sea coastline would not be as warm as those in the east would be.
Fiordland was set to be rainy and 15degC, while Westport and Greymputh would be be cloudy and rainy with a high of 16degC.
And it appeared Wellington would miss out on the warm weather instead copping fairly typical windy spring weather.
Next week cools down faster in the South Island on Tuesday, but the North Island stays fairly mild, Mr Duncan predicted.
While sunny warm weather might delight the summer lovers, the early high temperatures are also a warning.
Mr Duncan said such high temperatures a full five months out from the hottest time of the year may mean Australia would experience record-breaking summer heat and the bushfire season also looked to be severe.