Amit Singh, a senior forecaster at the Fiji Meteorological Service, said the system, TD17F, made landfall on the northern island yesterday, bringing with it heavy rain and strong winds.
He said Vanua Levu received 24-hours of very heavy rainfall, which has flooded low-lying areas and damaged crops, according to reports received by the service.
"Looking at the rainfall at different places, there's been a significant amount of rainfall reported," said Mr Singh in an interview on Sunday. "Some places had more than 310mm in 24-hours, and some over 200, and some over 100."
Local media were carrying reports of the Qawa river, which runs near the island's main town of Labasa, bursting its banks on Sunday, flooding parts of the town.
Fiji Village reported police in the town saying the Labasa Civic Area, Bulileka, Soasoa, Siberia, Wailevu and the Airport road were all flooded.
The system is the latest major tropical disturbance to affect Fiji since the category five Cyclone Winston caused extensive damage to much of the country nearly two months ago.
Two weeks ago, two tropical depressions and a category three cyclone, Zena, caused widespread flooding on the main island of Viti Levu, one of the areas worst-affected by Cyclone Winston.
However, Amit Singh said this weekend's tropical depression has left areas hardest-hit by the cyclones largely unaffected.
Mr Singh said the system was now moving southeast over the Lau group of islands and was steadily weakening.
Severe weather warnings for the country were expected to be cancelled early on Sunday afternoon, he said.
Pic courtesy Ezekial Ali/FijiVillage