The Fiji Meteorological Services says a heavy rain warning for the Northern Division and Northern Lau Group is now in force for the rest of the Fiji Group.
In a statement, the Nadi Weather Office said Tropical Disturbance TD12F which lies to the west of Vanuatu is expected to gradually drift east-southeast.
The low pressure system is gradually approaching the group from the northwest and rain developing in the afternoon and becoming frequent and heavy from later today.
The weather office warns of flash flooding for all flash flood-prone areas, small streams, and low-lying areas of Vanua Levu and is now in force for all flash flood-prone areas, small streams, and low-lying areas of Viti Levu.