A tropical cyclone could bring wind gusts of up to 120km/hr to New Zealand tomorrow, new predictions show.

Latest updates from the Fiji Metereological Service show Tropical Cyclone Zelia retaining Category 1 cyclone status through Tuesday.

Weatherwatch.co.nz head weather analyst Philip Duncan says that means it could bring sustained winds of 65km/hr and gusts of 120km/hr as it nears the upper North Island.

But the fact the strongest winds are near the centre of the cyclone may save the country from the worst of the storm, he says.

"The severe gales might only extend one or two hundred kilometres from the centre, so if the storm remains more than that distance from land before being downgraded you can see how many regions will miss the damaging winds altogether".

"It's certainly one to watch and plan accordingly but most New Zealanders will experience just a fairly short lived spell of windy, wet, weather and by Wednesday the sun starts to come back out" he says.

Earlier predictions showed Tropical Cyclone Zelia likely to weaken substantially before hitting the west coast of New Zealand.

Recent satellite images showed the eye of the storm had started to disappear, reducing its potential impact.

Tropical Cyclone Vania, which lashed Vanuatu and New Caledonia last week, is also expected to die down before hitting New Zealand, Mr Duncan says.

It too should be no worse than a normal low pressure weather system, despite projections it could bring heavy rains and flooding to Northland and Coromandel, he says.

"The positive is that they will move across New Zealand very quickly and be gone by Thursday. Most places will only have a day or two of off and on rain and some wind.

"But there is good news - the system is predicted to drop rain over thirsty farms in both islands."

Both systems are expected to hit New Zealand tomorrow or Wednesday morning.

Zelia is expected to pass over the North Island and potentially the upper South Island while the remnants of Vania will push into the South Island, weatherwatch.co.nz reports.

Only Norfolk Island, an Australian island 700kms north west of New Zealand with a population of 2100, could get hit hard by Tropical Cyclone Zelia, it predicts.