Those planning barbecues or outdoor activities this weekend should take advantage of the warm weather but be prepared for cloud and the chance of rain.
As sweltering temperatures set in across Central Otago, the rest of the country is also expected to get a fair deal of sunshine over the next few days.
"The next few days are looking really nice, with a nice ridge of high pressure bang on top of New Zealand which is perfect for this time of year and gives us these beautiful weather days," MetService communications meteorologist Lisa Murray said.
"If you look at a satellite image it is crystal clear over NZ which is quite impressive."
Niwa Weather reported that Cromwell reached 31.6C at 3pm today, making it the warmest spot in New Zealand.
This was the second-warmest spring temperature in the town on record since 1949, while 24 of the last 31 days in the town have been warmer than 20C.
Alexandra and Wanaka got to around 28C and will be the same again tomorrow and Friday. A southerly due to hit over the weekend will drop these temperatures to about 24-25C.
Christchurch and Wellington are looking at temperatures in the low 20s, with this dropping down to 18-19C over the weekend.
As the southerly moves up the country, the East Coast and the central plateau area of the North Island could also get a few showers.
Auckland isn't expected to be affected and will sit at a steady 22-23C until Sunday.
"What you guys are really going to notice is the humidity so get the fans out or the air con ready," Murray said.
"There won't be any extremes or records broken but it will be hot and humid. That humidity should start on Friday and carry through until Monday.
"Next week is looking like a dry, warm week as well but the first week of December may end the summer spell and bring with it another bout of wet weather."
According to the Niwa seasonal outlook temperatures are expected to sit above average across all of New Zealand for the next two months.