At 8.30am Mosgiel was the coldest centre in the country, according to MetService, on a very chilly -6.7degC.
Dunedin city was a relatively balmy 5C.
Unofficial weather station data on the MetService website showed Middlemarch at -8C, and much of inland Otago in the -3C to -5C range.
Parts of inland Canterbury such as Twizel and Tekapo were sitting around -6C as well.
In most places it's being reported as a dry cold, with few issues for motorists on the region's roads. Grit and CMA have been applied in parts of Central Otago and Queenstown Lakes.
All highways and main roads are open. The Danseys Pass road is restricted to four-wheel-drives, because of snow.
A generally settled day is forecast across the country today, before conditions change and wet weather moves in for many heading into the weekend.
MetService this morning issued heavy rain watches for much of the country.
The culprit was a front preceded by a moist northerly flow expected to move slowly east across New Zealand on Thursday and Friday.
"It takes it time to run in from the west on Thursday," MetService meteorologist John Law said.
Fiordland, north of Doubtful Sound and the ranges of the Westland District was forecast to be hit first, with periods of heavy rain from 11am on Thursday.
Northland would start to see the wet weather hitting the area in the afternoon from 1pm on Thursday.
Meanwhile, the heavy rain would sweep across Auckland, including Great Barrier Island and the Coromandel, Bay of Plenty and Rotorua later in the evening on Thursday with possible thunderstorms.
Taranaki and Tasman, northwest of Motueka also had heavy rain watches in place from Thursday evening onwards.
- ODT Online/RNZ
