Forecasters in Fiji say damaging gale force winds are expected to affect the northern parts of Vanuatu later today.
A tropical depression has hit the Fiji island of Rotuma with strong winds and heavy rain.
The Fiji Meteorological service says heavy rain, including squally thunderstorms are expected to hit the north of Espiritu Santo this evening.
It expects flooding including sea flooding of low-lying areas and damaging, heavy swells.
Forecasters say the potential for the system to develop into a tropical cyclone within the next 24 to 36 hours is moderate to high.