A Heavy Rain Alert is now in force for the Fiji Group.
The Nadi Weather Office says an active trough of low pressure with the associated clouds and rain is expected to affect the Fiji group from the west later tomorrow.
Meanwhile, a moist east to northeast wind flow prevails over the country.
They say there will be occasional to periods of rain and few thunderstorms over the Fiji group from later tomorrow.
The Weather Office says localised heavy falls may lead to flash flooding of low lying flood prone areas as well as small rivers and streams.