Otago residents can expect a bit of “weather whiplash” over the next four days, as temperatures switch between hot and cold.

The mercury is expected to reach 17˚C in Dunedin and Oamaru and 18˚C in Alexandra and Cromwell on Saturday, before strong southwesterlies send temperatures plummeting, bringing rain and snow to much of Otago and Southland on Sunday. 

MetService meteorologist Katie Lyons said Saturday’s warm weather was created by the foehn wind effect, where strong northwesterlies rise up and over the Southern Alps and then come down into Otago, bringing quite warm temperatures for this time of year.

“For places on the western side of the country, it’s nowhere near as warm as what you guys on the east coast are going to get.

“You east coasters are in for a nice warm couple of days, albeit somewhat windy with a few showers popping through.

“But then on Sunday, we get sort of a tilt in the winds, which swing around to the west-southwest.”

A strong wind warning had been issued for Southland (south of Gore) and Stewart Island, for 12 hours between 4am and 4pm on Sunday, she said.

Severe gale westerlies could gust to 120kmh in exposed places, potentially damaging trees, powerlines and unsecured structures.

Driving might also be difficult, especially for high-sided vehicles and motorcycles.

A strong wind watch has also been issued for Dunedin and the Clutha area, between 6am and 6pm on Sunday, and MetService said there was a high chance of it also being upgraded to a warning.

Mrs Lyons said the “tilt” would bring much cooler air and showery conditions.

“Those two things combined could lead to some snow about the South — not huge amounts, but some top-ups for the ski fields, as well as maybe some of those higher mountain roads.

“For the majority of people, it’ll just be showers.”

But then on Monday and Tuesday, the warm temperatures would return to about 17˚C or 18˚C.

“We’re heading into spring, so we do tend to get these very quick moving features, which means chopping and changing between warm air ahead of a cold front, and then colder air behind it.

“It’s not unusual for this time of year, but yeah, it does feel like a bit of weather whiplash.”

At this stage, temperatures for the remainder of the week are expected to be in the low to mid-teens. 

People are urged to keep up-to-date with the latest forecasts, particularly on Sunday.

john.lewis@odt.co.nz