The category three system is on track to hit the island of Ouvea with very destructive winds.
A level two alert has been in force for Ouvea and Lifou as well as coastal areas of the main island, which means that people have to be inside their homes or in shelters.
The maximum alert will be extended to the rest of the east coast and to the island of Mare at 5pm today.
Authorities have shut down the water supply in Hienghene, Poindimie and Canala to protect those communities from storm contamination.
