Temperatures soared to 29.6degC, making it the hottest place in the country, but the heat brought with it a spate of fires across Otago and Southland.
MetService forecaster Gerard Bellam said Dunedin’s close-to-record temperature — which is 30.2degC for this time of year — was closely followed by other South Island centres.
Invercargill, Gore, Wanaka and Queenstown sat around 24degC, and Oamaru reached 26degC.
Three helicopters fought a large gorse fire in a gully north of Dunedin that had covered 5ha by 6.30pm.
A Fire and Emergency New Zealand spokeswoman said wind and hot weather were contributing to the blaze, close to State Highway 1 south of Waikouaiti.
Crews from Waikouaiti, Palmerston, Hampden, Willowbank, Waitati and a Dunedin command unit responded, and the helicopters used monsoon buckets to dump water on the blaze. No properties were compromised.
Earlier, a burn-off got out of hand due to high winds at the St Clair Golf Club, in Hillhead Rd.
An Otago Daily Times photographer at the scene said it appeared the fire was in piles of slash or scrub beside the 12th fairway.
Crews were also kept busy by a gully fire in Balclutha that covered about 2ha, as well as a grass fire in Middlemarch.
While it was a warm start to Labour Weekend for the South, wild weather is set to end it, which may help ease dry conditions.
The "warm to hot" weather and gusty northwesterly winds quickly changed to a cold and wet spell, Mr Bellam said.
A heavy rain warning was issued for part of the lower South Island overnight, including Fiordland, and a heavy rain watch was issued for parts of Otago.
But that was good news for some, he said.
"Much of Otago, especially as you look up towards North Otago. is quite dry at the moment. We have got quite a soil moisture deficit on the farms there.
"For some people it is a blessing; for other people it is a bit of a curse if you are on holiday."