A number of Air New Zealand flights have been cancelled, after severe gales hit southern and central parts of the country.

The airline said strong winds had impacted its operations in Wellington, Palmerston North, New Plymouth, Blenheim, Invercargill, Dunedin and Queenstown.

Wellington Airport said two flights were cancelled and two others diverted early on Sunday morning.

MetService meteorologist Gerard Bellham said central parts of the country were feeling the effects of "strong, blustery winds". Those severe gusts hit 168 km/h on Sunday morning at Wellington's Mt Kaukau.

An orange strong wind warning is in place until at least 8pm on Sunday for the Tararua district. Severe gales gusting up to 120km/h were possible.

That meant the wind could damage trees, powerlines and unsecured structures. It could also make driving difficult, especially for high-sided vehicles and motorbikes.

A strong wind watch is also in place until at least 9pm for inland Hawke's Bay, around and south of State Highway five.

West to northwest winds could approach severe gales in exposed places, Metservice said.

The wind had also been responsible for widespread power outages across the motu on Sunday, Bellham said.

More than 650 customers across the Wellington region had been affected. Almost 400 homes were without power earlier in the day in the Wairarapa, as well as another 200 in Manawatū.

Down south, more than 700 homes had unplanned outages in the Marlborough area, and more than 300 homes in Tasman experienced power outages early Sunday morning.

Almost 400 homes along the West Coast, including Hokitika and Wahapo, experienced wind-related outages earlier in the day. About 20 homes in Christchurch were affected too.

Bellham said better weather was on the horizon, with "spring-like" conditions ahead in the coming days.

Most of the North Island is forecast to be fine this week, with cloudy periods ahead for western parts of the island, becoming isolated showers later on in the week.

The South Island is not so lucky. Heavy rain is possible in western and southern parts of the island from Tuesday. Canterbury and Otago could even see snow on the hills from Thursday.