With high winds across New Zealand today, police are warning motorcyclists and drivers of vehicles with a high point of gravity to take care and drive to the conditions.

Vehicles with a high point of gravity include busses, trucks and vans.

"With high winds across Manawatu, Whanganui to Ruapehu, and Taranaki, Police want everyone to arrive safely at their destinations," says a police spokesperson.

"Drive to the conditions, and stop and wait if you feel unsafe."

A strong west to northwest flow is covering the country.

"Fast moving embedded fronts are bringing bursts of heavy rain to western parts of the South Island, with significant spillover into the Canterbury and Otago headwaters," says a MetService spokesperson.

"Gale or severe gale west to northwest winds are expected to affect many areas in central and southern New Zealand."

Warnings and Watches are in force for heavy rain and strong winds.

MetService is forecasting severe northwest gales across parts of New Zealand in the week ahead, with heavy rain expected for the west of the South Island and severe northwest gales for central and southern New Zealand.

A ridge of high pressure is moving onto northern New Zealand from the Tasman Sea on Tuesday bringing settled weather, then moves away to the east on Thursday, says a MetService spokesperson.

"Meanwhile, a strong and moist northwest flow becomes established over southern New Zealand during Tuesday and early Wednesday, then a complex trough of low pressure crosses the South Island from the west on Friday.

There is high confidence rainfall amounts will reach warning criteria about Fiordland and Stewart Island late Wednesday and Thursday, and also about much of Westland and the Otago/Canterbury headwaters on Thursday and Friday.

There is moderate confidence a heavy rain warning being required for the far north of Westland, Buller, far west Tasman, Nelson Lakes and also the Richmond and Bryant ranges on Friday.

Lastly, there is low confidence of heavy rain for Southland and much of Otago on Thursday and Friday and about Mount Taranaki/Taranaki Maunga on Friday.

Additionally, there is high confidence of severe northwest gales about Canterbury, Otago, Southland and southern Fiordland on Wednesday and Thursday.

There is moderate confidence of severe northwest gales about Wairarapa, Wellington and Marlborough on Thursday and Friday.

Please stay up to date with forecasts in case any changes are made to the current warnings or watches, or new ones are added.

Heavy Rain Watch
Area: Nelson Lakes
Valid: 12 hours from 10:00am Sun 17 Sep to 10:00pm Sun 17 Sep
Forecast: A period of rain with some heavy falls, and amounts may approach warning criteria. Thunderstorms possible.

Area: North Otago, Dunedin and Clutha north of Balclutha
Valid: 3 hours from 9:00am Sun 17 Sep to 12:00pm Sun 17 Sep
Forecast: A period of rain with heavy falls possible, and amounts may approach warning criteria.

Strong Wind Watch
Area: The Central North Island high country from south of Lake Taupo to Taihape

Valid: 14 hours from 4:00pm Sun 17 Sep to 6:00am Mon 18 Sep
Forecast: West to northwest winds may approach severe gale in exposed places.

Area: Horowhenua and the Kapiti Coast
Valid: 16 hours from 9:00am Sun 17 Sep to 1:00am Mon 18 Sep
Forecast: Northwest winds may approach severe gale in exposed places.

Area: Tasman northwest of Motueka
Valid: 12 hours from 9:00am Sun 17 Sep to 9:00pm Sun 17 Sep
Forecast: Northwest winds may approach severe gale in exposed places.

Area: Canterbury Plains and Christchurch including Banks Peninsula
Valid: 11 hours from 9:00am Sun 17 Sep to 8:00pm Sun 17 Sep
Forecast: Northwest winds may approach severe gale in exposed places.

Area: Otago excluding Clutha
Valid: 24 hours from 9:00am Sun 17 Sep to 9:00am Mon 18 Sep
Forecast: West to northwest winds may approach severe gale in exposed places.