Weather: Thunderstorms, shock 0C warnings for New Zealand

Temperatures are set to plummet as several winter-like cold snaps hit New Zealand this week.

MetService is issuing severe weather watches with rain and gale force winds forecast to sweep up the South Island on Monday before moving across the North Island on Tuesday.

"An active cold front moving up the South Island today is forecast to deliver heavy rain and generate strong winds over many parts of the island," says MetService meteorologist Andy Best.

"The front moves across the North Island on Tuesday with severe weather watches and orange warnings in place for many areas as well as the possibility of thunderstorms for parts of the upper North Island."

This will be followed by a blast of cold air from the Southern Ocean moving onto the South Island on Wednesday morning, bringing "much colder weather in its wake".

"Freezing levels lower dramatically, bringing a distinct wintery feel to conditions over the far south of the country," MetService says.

This could drive temperatures down to as low as 0C, with snow forecast to around 400 metres over Southland, Fiordland and Otago during Wednesday. 

"The maximum temperature in Dunedin on Wednesday is expected to be only 9C and just 8C in Invercargill," Best says.

"Temperatures overnight Wednesday/Thursday are expected to fall to 0C in Christchurch and Blenheim, around 2 or 3C in the northern Wellington suburbs and down to 0C at Masterton as the cold air pushes farther north."

Thursday will be a cold and windy day nationwide with a strong sou'west flow covering much of New Zealand.

Newshub.