A complex trough of low pressure is forecast to move northeast across the North Island on Sunday, says a MetService weather forecaster.

This trough will be spreading an unsettled south to southeast flow over the North Island, while a ridge of high pressure builds farther south.

"On Sunday, there is low confidence of warning amounts of rain for Gisborne and Hawke's Bay about and north of Napier, and low confidence of severe gale southeasterlies about eastern Bay of Plenty and northern Gisborne.

"In addition, there is low confidence of severe gale southwesterlies affecting Auckland and Northland later Sunday into early Monday."

Unsettled westerlies then cover New Zealand from Monday through to Wednesday, with low confidence of severe gale westerlies about central Hawke's Bay through to northern Wairarapa, and moderate confidence of severe gale west to southwesterlies affecting Dunedin, Clutha, Southland and southern Fiordland.

Finally, a front embedded in the westerly flow is forecast to approach the far south of New Zealand late Wednesday, with low confidence of warning amounts of rain falling in Fiordland.