Niwa meteorologist Ben Noll said even though the high temperatures last month broke records, it was more difficult to break records in summer.
"When you go into the summer season average temperatures increase, so it’s harder to break the records."
Cromwell was the top hot spot of the region in recorded areas this week, hitting 31.8degC on Tuesday.
Cromwell’s maximum temperatures were above 25degC for the entire week.
"Cromwell has been the epicentre of the heat over the last month and a-half," Mr Noll said.
The MetService gathered data on records for Queenstown and Wanaka.
MetService meteorologist Ravi Kandula said 31degC for Wanaka on December 6 was hot, as the mean maximum for the month was 21.7degC.
It was the same for Queenstown — the temperature of 29degC on December 6 was high given the mean maximum for the month was 21.7degC.
Mr Kandula said the light winds and lack of sea breezes in inland areas meant the temperatures were much warmer than in coastal areas.
Even so, there was a slight heatwave this week on the coast as Dunedin, Oamaru and Balclutha hit their week’s high on Monday at 24degC, 25degC and 23degC respectively.
Mr Kandula said the forecast in Central Otago might not be as hot next week.Next week’s highs would be more in the 20s range for most of the week, which was normal for December.
The weather also looked unsettled because of several fronts that would move through. He said people should expect showers at times.
