The Nadi Weather Office says the system is slowly moving over the Solomon Islands and is expected to track southeast, becoming a Tropical Depression from tomorrow.
As the system tracks southeast over Vanuatu, it is expected to enter Fiji waters by Tuesday.
The Weather Office says that as the system reaches Fiji, rain is expected to become more frequent and heavy, with fresh to strong gusty winds from Tuesday into Wednesday.
There will also be a high chance of flooding, including river flooding.
The Weather Office advises that effects may begin from Monday night into Tuesday.
Hazard flash flooding may occur due to heavy rain, based on rainfall forecast models and weather radar observations.
Heavy Rain Alert and Flash Flood Alert remains in force for the whole of Fiji, as a trough of low pressure continues to affect the group, bringing heavy rain at times.
Expect flooding of drainage systems, small streams, low water bridges, Irish crossings, roads, and properties in low-lying areas.
Residents are urged to take all necessary precautions, as heavy rain is expected to continue throughout the weekend due to the trough of low pressure associated with Tropical Disturbance TD03F.
Do not leave preparations to the last minute.
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