Christchurch residents were warned to brace for a sharp change in the weather this weekend, with cold frosts giving way to powerful northwesterly winds and severe weather warnings across much of the South Island.

MetService forecaster John Law said Friday evening would be clear and calm, but temperatures were set to plunge overnight.

“I wouldn’t be surprised if we see Christchurch dipping down towards freezing tonight. So a cold and frosty start to the weekend, but generally dry and clear. We’ll need those extra layers, especially if you’re up early for that morning dog walk,” Law said.

While Saturday morning is expected to begin fine and sunny, cloud is forecast to build during the day before strong northwesterly winds arrive.

“I think for many of us the talking point of this weekend will be some pretty strong winds that arrive late in the day on Saturday and then through in towards Sunday, with a pretty blustery story in store,” Law said.

MetService has already issued severe weather watches and warnings covering much of the South Island. Heavy rain is forecast for the West Coast, with strong winds spreading across Southland, Otago, Canterbury and Marlborough.

“Some of the strongest winds, I think, will be through the Canterbury High Country, where we could find gusts of wind perhaps 140 kilometres an hour in the most exposed areas. Some of those stronger winds will make their way down towards Christchurch as well, so even the Canterbury Plains and Christchurch have a strong wind watch on Sunday,” Law said.

Conditions are expected to ease on Monday, bringing a brief reprieve.

“I think we will find that does start to clear away. Monday gets a bit of a break as well. But I think for us, the windiest time will be that Sunday,” Law said.

For more information, residents are advised to check the latest updates at metservice.com.