Weather: 'Rapid warming' on the way

Labour Weekend is going to be warm for most of the country as this week's unsettled weather moves away.

Some places could be up to 15 degrees warmer on Saturday than they were on Thursday, forecaster WeatherWatch says.

The rise is due to a northwest flow from Australia and the sub-tropics and will mostly affect the South Island.

Christchurch is expected to hit 19C on Saturday, while Dunedin will be the warmest at 22C. Further north, Auckland will be 18C and Wellington will be 16C.

NIWA's weather forecasting arm agrees with WeatherWatch and has forecast a warmer weekend than the last few.

"Who's excited for the upcoming long weekend with warmer temperatures (finally!) returning," it said on Twitter. 

MetService says the long weekend will be wetter than 2018's, with some possible rain in the lower West Coast and gales in the South Island high country.

No severe weather warnings or watches have been issued.