Weather: 'Dangerous' 8m waves slam New Zealand

New Zealand's coast is being slammed by "dangerous" waves on Monday as gale-force winds continue to whip up large swell.

"Dangerous waves are also impacting the country as we go through Sunday and Monday," Weather Watch says.

"Not good days to be on the water with not only large waves in many places but also gale force winds in marine areas too until later on Monday."

WeatherWatch head weather analyst Philip Duncan says the "massive swells" will affect some of Auckland's more popular beaches, including Piha, Muriwai and Bethells Beach.

"There are waves of around eight-metres around the Chatham Islands. Stewart Island has waves of six-metres as do areas of Southland," he told Newshub.

"The west coast still has three to four-metre waves as far up as Auckland."

Duncan says the windy south-westerlies are connected to airflow coming out of Australia.

These are expected to die down as a large high pressure system crosses New Zealand from later today until early next week.

Newshub.