Unsettled weather is forecast over New Zealand in the coming days.

A strong west to southwest flow is expected to bring showers to some parts of the country.

"An active trough embedded in this flow is expected to affect the country on Friday and Saturday, then the flow turns northwest over southern New Zealand on Sunday ahead of another active trough which should move quickly over southern and central New Zealand from the southwest on Monday, followed by strong south to southwesterlies," says the latest update from the MetService.

"There is moderate confidence of severe westerly gales for the Tararua District and Hawke's Bay south of Cape Kidnappers on Friday plus Saturday morning, and again on Monday.

"There is also moderate confidence of severe northwest gales for the Canterbury High Country on Friday and again on Monday."

The MetService says on Saturday, there is moderate confidence of severe west to southwest gales for Northland, Great Barrier Island, Auckland, Waikato, Coromandel Peninsula and western Bay of Plenty.

There is also moderate confidence of severe southwest gales for Mahia Peninsula and near the coast of Tairawhiti/Gisborne.

"On Sunday and Monday, there is moderate confidence of rainfall accumulations reaching warning criteria in Westland, especially about the ranges, and low confidence for central and northern Fiordland.

"There is also low confidence on heavy rain for Buller on Monday.

"Also on Sunday and Monday, there is low confidence of severe northwest gales for Southland, Stewart Island and Clutha.

"On Monday, there is moderate confidence of severe northwest gales for Wairarapa, Wellington and the Marlborough Sounds, low confidence of severe westerly gales for southern Manawatu to the Kapiti Coast and northwest Tasman, and also low confidence of severe southwest gales about Banks Peninsula."