MetService is warning most of the country is heading into a "fairly volatile looking weather week", with the first of two systems hitting New Zealand on Monday.

Head of weather news Heather Keats said much of New Zealand will be impacted, with a vast number of significant orange warnings for both heavy rain and northwest gusts issued on Sunday.

"We're talking gusts up to 130km/h for the Canterbury high country and the foothills of the Canterbury Plains, as well as Wellington, Wairarapa, and the Tararua district," she said.

"120km/h for Otago, for the deep South, and for Marlborough.

"The heavy rain is expected to be the most significant for the western side of the Alps, as per usual, however, there will be spill over into the headwaters of the Canterbury and Otago lakes and rivers."

Heavy rain warnings stretch from Fiordland to parts of Marlborough.

Keats said the front will move up the South Island on Monday before starting to weaken as it crosses over the North Island in the early hours of Tuesday,

But that was not the worst of it, with "an even more impactful weather system arriving on Thursday," Keats said.

"As that system moves up and over the country, it will weaken as well but it's going to take a little longer to weaken.

So, we are expecting some more widespread heavy rain and some gale nor'westers to the North Island as well on Thursday and Friday," she said.

There would be more warnings issued closer to the time, she said.

"The potential is there for this to be a highly impactful event."

"Gale northwesterlies tied in with a very significant front and a deep low pressure system to the far south of the country which will bring cold southwesterlies.

Thursday will be a big day in the south and for central New Zealand."

"On Friday, that front will move over the North Island, it is weakening, but still some wet and windy weather to track with it," Keats said.

Keats said the weather the country is experiencing was typical spring weather.

But she says with little reprieve between the fast moving fronts, it is feeling like a very active spring.

"Yes, it will calm down, but it doesn't look likely this week and maybe even to next week as we see again those fast fronts as they cross over us," Keats said.

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