The Fiji Metrological Service says Cyclone Gita is already affecting the waters of Noumea as the category 3 system heads towards New Caledonia.
Forecaster Rajneel Prasad said gale force winds may affect Noumea as the cyclone approaches.
He said the location of tropical cyclone Gita was 480km east of Noumea at 6am (Fiji time) this morning.
It is expected to track west and southwest from its current location and will pass over the southeast islands of New Caledonia over the next day or so.
Activities at sea are banned on New Caledonia's Isle of Pines and people were being advised to board up their houses and secure their livestock.
A pre-alert remains in place for the rest of the territory.
During the night to Saturday, it is expected to pass between 100 to 150 kilometres south east of the Isle of Pines as it veers into the Tasman Sea.
The system was forecast to bring winds gusting up to 120 kilometres an hour to the Isle of Pines by this evening.
Winds in excess of 100km/h are possible for the southern part of the island of Grande Terre.
Heavy rain is expected in the south of New Caledonia in the night to Saturday and Mr Prasad said storm surges and damage to infrastructure are likely.
"We do expect some storm surges in this. And since it's a category 3 system it's also a hurricane, it's a category 3 system that is heading towards them, and we are expecting damages to infrastructure too."
Mr Prasad said on this track the cyclone is likely to impact New Caledonia for the next 30 - 48 hours.
MetService New Zealand said Gita was likely to head towards New Zealand early next week.