22 May 2017

Mercury plummets across NZ

9:36 am on 22 May 2017

New Zealanders woke to plummeting temperatures, below -6°C in some places, and while the bad weather from the weekend is set to clear today it will get worse again later in the week.

A frosty morning in the Waikato.

A frosty morning in the Waikato. Photo: Supplied

Middlemarch, near Dunedin, was the coldest place in the country, with the president of the town's museum, Irene Ramsay, saying temperatures had risen this morning by .2°C to -6.1°C.

Hamner Springs and Molesworth were bracing against -6°C too.

Sam Stoddart, who owns the Blacks Hotel in Ophir said temperatures were down to about -4°C in the Central Otago settlement.

Snow closed the Desert Road overnight Saturday and Sunday morning.

MetService meteorologist Sarah Garlick-Mercer said there had been more snow down south and some very cold temperatures overnight.

"We had some good snow down in the south and for the central plateau of the North Island too, and after this clearance that we got yesterday we had some really cold temperatures overnight."

Thing were expected to remain cold over the week.

"Fairly settled today after our cold start but then things look to be getting a bit more unsettled - doesn't look like any major weather systems heading our way but not fine weather for the rest of the week.

Over the weekend, massive waves were pounding the coastline from Gisborne to Wellington, cancelling ferries and raising fears the waves could damage sea walls.

Southwest gales brought the impressive swells as high as 11m across Cook Strait.

The swells have now eased but the cold weather is still about.

Niwa principal forecaster Chris Brandolino told Morning Report there were both high and low pressure systems over the country.

"Imagine putting your thumb over a garden hose, you have the water flowing out but now you've decreased the area for that water to flow so it has to accelerate.

"That's the same thing with the air, and that strong wind because of the pressure gradient, it produced the big waves."

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