The National Weather office states a trough of low pressure is approaching from the north and west.
In a bulletin released at 5:30am today, Fiji Met said the system, accompanied by clouds and rain, is expected to affect the country from later today through to Monday.
There will be cloudy periods with some showers are forecast for Serua-Namosi, Navua-Suva-Nausori, Tailevu-Naitasiri-Ra, Cakaudrove and Southern Bua provinces, as well as Kadavu, the Lau and Lomaiviti groups, and nearby smaller islands.
Rainfall is expected to increase in frequency and intensity from later tonight across most areas.
For Monday, widespread rain and isolated thunderstorms are forecast for most of the country.
Localised heavy falls may lead to flash flooding in low-lying and flood-prone areas.
