Tropical cyclone Iris, a category one, was moving west northwest at 15 kph, and was hundreds of kilometres northwest of the capital, Port Vila.
The Vanuatu Met Service said heavy rainfalls will affect Northern and Central islands today and continuing tomorrow with flash flooding possible over low lying areas, and areas close to the river banks.
It said seas would become rough to very rough with moderate to heavy swells over Northern and Central waters.
A severe weather warning was current for areas mentioned.
A strong wind warning had been issued for Northern and Central coastal waters of Vanuatu.
People over Northern and Central Islands are advised to listen to Radio Vanuatu and all other radio outlets to get an update information on this system.