New Zealand will escape the worst of twin cyclones in the Pacific - but you'd better get your brollies ready for some rain next week.

It was earlier feared Cyclone Winston and Cyclone Tatiana could unleash their fury on New Zealand.

But that now seems unlikely, with WeatherWatch head analyst Philip Duncan saying Cyclone Winston - upgraded yesterday to a category 4 - was turning northeast towards the southern, thinly populated parts of the Fiji islands.

"It doesn't affect any nation because it's so far away from everybody at the moment," he said.


Cyclone Tatiana, which had been threatening New Caledonia, has fizzled out.

Cyclone Winston's impact on New Zealand is likely to be restricted to heavy waves down the east coast of the North Island from Cape Reinga to Tauranga on Monday and Tuesday.

Duncan said beachgoers in northeast parts of the North Island should be wary of potential big waves as they enjoy calm, fine weather.

"The swells will be somewhere in the two-to-three-metre range," he said.

"The weather could be beautiful and calm as anything, but the waves could be picking up. Sometimes you get the odd big wave coming in. That's exactly what sweeps people off the rocks.

"We are not saying don't go in the water - it's summertime - but use common sense, so if you know a beach that is safer, such as Cook's Beach, those are the ones to use."

WeatherWatch is forecasting fine weather across the North Island today, through to the first half of next week.

South Islanders are also expected to enjoy great summer weather.


But from Wednesday, a weather system coming in from the Tasman Sea is expected to bring rain to most areas.

Temperatures are expected to remain in the mid-20s, and high humidity is also expected.

"The North Island could be in for some good downpours," Duncan said, "and there's a chance that we could get some weather warnings, more in terms of the rain."