Temperatures have plummeted in the South Island overnight with some waking to conditions as low as -7C.
WeatherWatch says as of 6am Wednesday, areas of the Canterbury High Country remained well in the negatives - Twizel being the coldest at -7C and Fairlie -6C.
"Staggering for April which these temperatures are more associated with June, July, and August," local forecaster Mackenzie Country Weather said. Further up the South Island, Christchurch fell to an overnight low of 0C.
It was cold in the North Island too with many areas dropping to single digits, according to MetService. Masterton dived to 3C and Palmerston North 6C.
It won't be quite as cold to start the day on Thursday however as temperatures largely return to normal. MetService says Auckland will see a low of 10C, Hamilton 6C, Wellington 12C, Dunedin 11C, and Christchurch 6C.
But there'll be showers across New Zealand on Friday. Southern parts of the North Island, including Wellington and Masterton, have been told to expect a southerly change.
"Another cool change zips up the country on Friday bringing a brief period of showers but with the high-pressure system just off the west coast, the impacts look to be fairly minimal," MetService said in a statement.